415 research outputs found
An Efficient Hybrid Planning Framework for In-Station Train Dispatching
In-station train dispatching is the problem of optimising the effective utilisation of available railway infrastructures for mitigating incidents and delays. This is a fundamental problem for the whole railway network efficiency, and in turn for the transportation of goods and passengers, given that stations are among the most critical points in networks since a high number of interconnections of trains’ routes holds therein. Despite such importance, nowadays in-station train dispatching is mainly managed manually by human operators. In this paper we present a framework for solving in-station train dispatching problems, to support human operators in dealing with such task. We employ automated planning languages and tools for solving the task: PDDL+ for the specification of the problem, and the ENHSP planning engine, enhanced by domain-specific techniques, for solving the problem. We carry out a in-depth analysis using real data of a station of the North West of Italy, that shows the effectiveness of our approach and the contribution that domain-specific techniques may have in efficiently solving the various instances of the problem. Finally, we also present a visualisation tool for graphically inspecting the generated plans
Soil CO2 emissions at Furnas volcano (São Miguel Island, Azores archipelago) - volcano monitoring perspectives, geomorphologic studies and land-use planning application
Carbon dioxide (CO2) diffuse degassing structures (DDS) at Furnas Volcano (São
Miguel Island, Azores) are mostly associated with the main fumarolic fields, evidence
that CO2 soil degassing is the surface expression of rising steam from the hydrothermal
system. Locations with anomalous CO2 flux are mainly controlled by tectonic structures
oriented WNW-ESE and NW-SE and by the geomorphology of the volcano, as
evidenced by several DDS located in depressed areas associated with crater margins.
Hydrothermal soil CO2 emissions in Furnas volcano are estimated to be ~ 968 t d-1.
Discrimination between biogenic and hydrothermal CO2 was determined using a
1
statistical approach and the carbon isotope composition of the CO2 efflux. Different
sampling densities were used to evaluate uncertainty in the estimation of the total CO2
flux, and showed that a low density of points may not be adequate to quantify soil
emanations from a relatively small DDS. Thermal energy release associated to diffuse
degassing at Furnas caldera is about 118 MW (from an area of ~ 4.8 km2) based on the
H2O/CO2 ratio in fumarolic gas. The DDS affect also Furnas and Ribeira Quente
villages, which are located inside the caldera and in the south flank of the volcano,
respectively. At these sites, 58% and 98% of the houses are built over hydrothermal
CO2 emanations, and the populations are at risk due to potential high concentrations of
CO2 accumulating inside the dwellings.
Keywords: Soil diffuse degassing; soil CO2 flux; emission rates; Azores archipelago
Long Time Series Of Fumarolic Compositions At Volcanoes: The Key To Understand The Activity Of Quiescent Volcanoes
Long time series of fumarolic chemical and isotopic
compositions at Campi Flegrei, Vulcano, Panarea,
Nisyros and Mammoth volcanoes highlight the occurrence
of mixing processes among magmatic and hydrothermal
fluids. At Campi Flegrei temperatures of
about 360°C of the hydrothermal system are inferred by
chemical and isotopic geoindicators. These high temperatures
are representative of a deep zone where magmatic
gases mix with hydrothermal liquids forming the gas plume feeding the fumaroles. Similar mixing processes
between magmatic fluids and a hydrothermal
component of marine origin have been recognized at
Vulcano high temperature fumaroles. In both the system
a typical ‘andesitic’ water type composition and high
CO2 contents characterizes the magmatic component.
Our hypothesis is that pulsing injections of these CO2-
rich magmatic fluids at the bottom of the hydrothermal
systems trigger the bradyseismic crises, periodically
affecting Campi Flegrei, and the periodical volcanic
unrest periods of Vulcano. At Campi Flegrei a strong
increase of the fraction of the magmatic component
marked the bradyseismic crisis (seismicity and ground
uplift) of 1982-84 and four minor episodes occurred in
1989, 1994 and 2000 and 2006. Increases of the magmatic
component in the fumaroles of Vulcano were recorded
in 1979-1981, 1985, 1988, 1996, 2004 and 2005
concurrently with anomalous seismic activity. Physicalnumerical
simulations of the injection of hot, CO2 rich
fluids at the base of a hydrothermal system, asses the
physical feasibility the process. Ground deformations,
gravitational anomalies and seismic crisis can be well
explained by the complex fluid dynamic processes
caused by magma degassing episodes. Sporadic data
on the fumaroles of other volcanoes, for example Panarea,
Nisyros (Greece), Mammoth (California), suggest
that magma degassing episodes frequently occur in
dormant volcanoes causing volcanic unrest processes
not necessarily linked to magma movement but rather
to pulsating degassing processes from deep pressurized,
possibly stationary, magma bodies
Carbon dixide emission in Italy: Shallow crustal sources or subduction related fluid recycling?
Anomalous non-volcanic CO2 release in central and
southern Italy has been highlighted by ten years of detailed
investigations on Earth degassing processes. Two regional
degassing structures are located in the Tyrrhenian sector
where more then 200 emissions of CO2 are located and has
been recently included in the first web based catalogue of
degassing sites (http://googas.ov.ingv.it). The total amount of
CO2 released by the two structures were evaluated to be >
2×1011 mol a-1 ( >10% of the estimated global volcanic CO2
emission). The anomalous flux of CO2 suddenly disappears in
the Apennine in correspondence of a narrow band where most
of the Italian seismicity concentrates. Here, at depth, the gas
accumulates in crustal traps generating CO2 overpressurised
reservoirs. These overpressured structures are, in our opinion,
one of the main cause of Apennine earthquake activation
processes. The results of these investigations suggested that
Earth degassing in Italy may have an active primary role in the
geodynamics of the region. What is the origin of gas? The
large extension of the degassing structures and petrologic data
suggested that the main source of gas is a mantle
metasomatised by the fluids produced in the subdacted slabs.
However, has been also hypothesised the presence of localised
crustal source of the gas. This matter will be discussed on the
base of unpublished isotopic data of the main gas emissions
First observations of the fumarolic gas output from a restless caldera: implications for the current period of unrest (2005–2013) at Campi Flegrei
The fumarolic gas output has not been quantified for any of the currently deforming calderas
worldwide, due to the lack of suitable gas flux sensing techniques. In view of resumption of ground uplift
(since 2005) and the associated variations in gas chemistry, Campi Flegrei, in southern Italy, is one of the
restless calderas where gas flux observations are especially necessary. Here we report the first ever
obtained estimate of the Campi Flegrei fumarolic gas output, based on a set of MultiGAS surveys
(performed in 2012 and 2013) with an ad-hoc-designed measurement setup. We estimate that the current
Campi Flegrei fumarolic sulphur (S) flux is low, on the order of 1.5–2.2 tons/day, suggesting substantial
scrubbing of magmatic S by the hydrothermal system. However, the fumarolic carbon dioxide (CO2)
output is 4606160 tons/day (mean6SD), which is surprisingly high for a dormant volcano in the
hydrothermal stage of activity, and results in a combined (fumarolesþsoil) CO2 output of 1560 tons/
day. Assuming magma to be the predominant source, we propose that the current CO2 output can be
supplied by either (i) a large (0.6–4.6 km3), deeply stored (>7 km) magmatic source with low CO2
contents (0.05–0.1 wt%) or (ii) by a small to medium-sized ( 0.01–0.1 km3) but CO2-rich (2 wt%)
magma, possibly stored at pressures of 100 to 120 MPa. Independent geophysical evidence (e.g.,
inferred from geodetic and gravity data) is needed to distinguish between these two possibilities
Metabolic aspects of cardiovascular diseases: Is FoxO1 a player or a target?
The O subfamily of forkhead (FoxO) 1 is a crucial regulator of cell metabolism in several tissues, including the heart, where it is involved in cardiac regulation of glucose and lipid metabolic pathways, and endothelium, controlling the levels of some relevant biomarkers in atherosclerotic process. Despite the growing understanding of FoxO1 biology, the metabolic consequences of FoxO1 modifications and its implication in CVD, atherosclerosis and T2DM are still not incompletely described. In this review we discuss how FoxO1 affects cardiovascular pathophysiology and which of its effects should be restrained or enhanced to preserve endothelial and heart functions
A Two-Phase ASP Encoding for Solving Rehabilitation Scheduling
The rehabilitation scheduling process consists of planning rehabilitation physiotherapy sessions for patients, by assigning proper operators to them in a certain time slot of a given day, taking into account several requirements and optimizations, e.g., patient’s preferences and operator’s work balancing. Being able to efficiently solve such problem is of upmost importance, in particular after the COVID-19 pandemic that significantly increased rehabilitation’s needs. In this paper, we present a solution to rehabilitation scheduling based on Answer Set Programming (ASP), which proved to be an effective tool for solving practical scheduling problems. Results of experiments performed on both synthetic and real benchmarks, the latter provided by ICS Maugeri, show the effectiveness of our solution
One year of geochemical monitoring of groundwater in the Abruzzi region after the 2009 earthquakes.
The presence of a deep and inorganic source of CO2 has been recently recognized in Italy on the basis of the
deeply derived carbon dissolved in the groundwater. In particular, the regional map of CO2 Earth degassing
shows that two large degassing structures (Tuscan Roman degassing structure, TRDS, and Campanian degassing
structure, CDS) affect the Tyrrhenian side of the Italian peninsula. The comparison between the map of CO2
Earth degassing and of the location of the Italian earthquakes highlights that the anomalous CO2 flux suddenly
disappears in the Apennine in correspondence of a narrow band where most of the seismicity concentrates. A
previous conceptual model proposed that in this area, at the eastern borders of TRDS and CDS, the CO2 from the
mantle wedge intrudes the crust and accumulate in structural traps generating over-pressurized reservoirs. These
CO2 over-pressurized levels can play a major role in triggering the Apennine earthquakes.
The 2009 Abruzzo earthquakes, like previous seismic crises in the Northern Apennine, occurred at the border of
the TRDS, suggesting also in this case a possible role played by deeply derived fluids in the earthquake generation.
Detailed hydro-geochemical campaigns, with a monthly frequency, started immediately after the main shock of
the 6th of April 2009. The new campaigns include the main springs of the area which were previously studied in
detail, during a campaign performed ten years ago, constituting a pre-crisis reference case. Almost one year of
geochemical data of the main dissolved ions, of dissolved gases (CO2, CH4, N2, Ar, He) and of the stable isotopes
of the water (H, O), CO2 (13C) and He (3He/4He), highlight both that the epicentral area of L’Aquila earthquakes
is affected by an important process of CO2 Earth degassing and that that the gases dissolved in the groundwater
reflects the input in to the aquifers of a deep gas phase, CO2- rich, with an high He content and with low 3He/4He
ratios, similar to the gases emitted by natural manifestations located in the northern Apennines which are fed by
deep pressurized reservoirs. Furthermore a systematic increase in the content of the deeply derived CO2 dissolved
in the aquifers occurred respect to the July 1997 samples. This increase, followed by a gentle decline of the
anomaly, can be compatible with the occurrence of an episode of deep CO2 degassing concurrently with the earthquakes.
The origin of this regional variation is under investigation and, at the present moment, an unambiguous
interpretation of the data is not possible because the lack of a systematic monitoring of the springs before the
seismic events and because eventual seasonal effects on observed variation in CO2 flux are still under investigatio
Diabetes influences cancer risk in patients with increased carotid atherosclerosis burden
Background and aims: Atherosclerosis and cancer share several risk factors suggesting that at least in part their pathogenesis is sustained by common mechanisms. To investigate this relation we followed a group of subjects with carotid atherosclerosis at baseline up for malignancy development.Methods and results: we carried out an observational study exploring cancer incidence (study endpoint) in subjects with known carotid atherosclerosis at baseline (n = 766) without previous cancer or carotid vascular procedures. During the follow-up (160 +/- 111 weeks) 24 cancer occurred, corresponding to an overall annual incidence rate of 0.11%. 10 diagnosis of cancer occurred in individuals with a carotid stenosis >50% (n = 90) whereas 14 in patients with a carotid stenosis <50% patients (n = 676) (p < 0.001). Respect to patients without cancer, diabetes was markedly more common in subjects with cancer diagnosis during the FU (37.3%vs75.0%, p < 0.001). After controlling for classic risk factors, carotid stenosis >50% (HR = 2.831, 95%CI = 1.034-5.714; p = 0.036) and diabetes (HR = 4.831, 95%CI = 1.506-15.501; p = 0.008) remained significantly associated with cancer diagnosis.Conclusions: to our knowledge this is the first study reporting a significant risk of cancer development in subjects with diabetes and high risk of cerebrovascular events, highlighting the need of a carefully clinical screening for cancer in diabetic patients with overt carotid atherosclerosis. (C) 2019 The Italian Society of Diabetology, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition, and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved
Active Degassing of Deeply Sourced Fluids in Central Europe: New Evidences From a Geochemical Study in Serbia
We report on the results of an extensive geochemical survey of fluids released in the Vardar zone (central-western Serbia), a mega-suture zone at the boundary between Eurasia and Africa plates. Thirty-one bubbling gas samples are investigated for their chemical and isotopic compositions (He, C, Ar) and cluster into three distinct groups (CO2-dominated, N2-dominated, and CH4-dominated) based on the dominant gas species. The measured He isotope ratios range from 0.08 to 1.19 Ra (where Ra is the atmospheric ratio), and reveal for the first time the presence of a minor (<20%) but detectable regional mantle-derived component in Serbia. δ13C values range from −20.2‰ to −0.1‰ (versus PDB), with the more negative compositions observed in N2-dominated samples. The carbon-helium relationship indicates that these negative δ13C compositions could be due to isotopic fractionation processes during CO2 dissolution into groundwater. In contrast, CO2-rich samples reflect mixing between crustal and mantle-derived CO2. Our estimated mantle-derived He flux (9.0 × 109 atoms m−2 s−1) is up to 2 orders of magnitude higher than the typical fluxes in stable continental areas, suggesting a structural/tectonic setting favoring the migration of deep-mantle fluids through the crust
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