•A novel numerical model solving the 2D-SWEs with porosity is presented.•The C-property along wet-dry fronts is ensured.•A spatially-distributed porosity field accounts for building distribution.•The ...model accurately predicts flooding scenarios involving large-scale domains.•A speed-up of 6 is achieved against a SWEs model resolving buildings on the mesh.
With the purpose of modelling at a large-scale river floods affecting urban areas, this work presents a numerical model solving the two-dimensional Shallow Water Equations with porosity. The distribution of buildings within urban fabrics is accounted for by means of a spatially-distributed field of the storage porosity parameter. The finite volume scheme conserves mass and it ensures the well-balancing property over complex topography. A structured multi-resolution grid is adopted for the domain discretization and the parallelization on Graphic Processing Units (GPUs) enables the reduction of the computational costs. Model testing is performed against experimental data and applications over real domains as well. The results provided by the proposed model agree with those obtained by resolving building footprints on a high-resolution mesh, meanwhile reducing the runtimes up to 6 times.
The capability of a GPU-parallelized numerical scheme to perform accurate and fast simulations of surface runoff in watersheds, exploiting high-resolution digital elevation models (DEMs), was ...investigated. The numerical computations were carried out by using an explicit finite volume numerical scheme and adopting a recent type of grid called Block-Uniform Quadtree (BUQ), capable of exploiting the computational power of GPUs with negligible overhead. Moreover, stability and zero mass error were ensured, even in the presence of very shallow water depth, by introducing a proper reconstruction of conserved variables at cell interfaces, a specific formulation of the slope source term and an explicit discretization of the friction source term. The 2D shallow water model was tested against two different literature tests and a real event that recently occurred in Italy for which field data is available. The influence of the spatial resolution adopted in different portions of the domain was also investigated for the last test. The achieved low ratio of simulation to physical times, in some cases less than 1:20, opens new perspectives for flood management strategies. Based on the result of such models, emergency plans can be designed in order to achieve a significant reduction in the economic losses generated by flood events.
Members of disadvantaged groups sometimes support societal systems that enable the very inequalities that disadvantaged them. Is it possible to explain this puzzling system-justifying orientation in ...terms of rational group-interested motives, without recourse to a separate system motive? The social identity model of system attitudes (SIMSA) claims that it is. SIMSA proposes that the system justification shown by a disadvantaged group (e.g., African American women) can sometimes support identity needs that are tied to a more inclusive (superordinate) in-group (e.g., Americans). There is already some supportive evidence for this proposition, but it is not yet clear whether: (1) such trends are visible in a wider range of disadvantaged contexts, and (2) this explanation also applies to those who are strongly invested in their subgroup (e.g., feminists). In two waves of a large nationally representative survey from 21 to 23 European states (Ntotal = 84,572) and two controlled experiments (Ntotal = 290 women), we found that: (a) system justification was positively associated with superordinate ingroup identification across multiple cases of disadvantage (Studies 1–3), (b) system justification increased when this inclusive identity was made more salient (Studies 2 & 3), and (c) system justification was visible even amongst feminists when they activated their superordinate (Italian) identity (Study 3).
Abstract Background Affective “Theory of Mind” (ToM) is the specific ability to represent own and others' emotional states and feelings. Several studies examined affective ToM ability in patients ...with Parkinson's disease (PD), using the “Reading the Mind in the Eyes test” (RMET). However, there has been no agreement as to whether or not affective ToM ability is impaired in PD and such discrepancy may be due to the heterogeneous clinical presentation of PD. Affective disturbance has been linked to the akinetic-rigid form of PD and to gait disturbances, like freezing of gait (FOG). Particularly, FOG has been associated with dysfunction in striatum ability of processing affective inputs. Here we hypothesized that the presence of FOG can be associated with impaired affective ToM ability in PD patients. Methods We evaluated ToM by means of RMET and executive functions using the Tower Of London (ToL) test in 29 PD patients (15 with FOG and 14 without FOG) and 19 healthy age-matched subjects. Results Our results showed that affective ToM is abnormal in PD patients, compared to healthy subjects and that it is more impaired in patients with FOG than in patients without FOG. Further, PD patients with FOG performed worse than PD patients without FOG on the ToL test. Conclusion The affective aspects of ToM can be associated to FOG in patients with PD, thus supporting the idea that FOG is caused by a complex interplay between motor, cognitive and affective factors, rather than being a pure motor problem.
In chronic hepatitis C, biopsy is the gold standard for assessment of liver fibrosis. Non-invasive markers have been proposed but their use is limited by diagnostic accuracy. Our aim was to increase ...the diagnostic performance of non-invasive markers of liver fibrosis by combining them in sequential algorithms.
One hundred and ninety patients with chronic hepatitis C were evaluated for AST to platelets ratio (APRI), Forns' index and Fibrotest at the time of liver biopsy and stepwise combination algorithms were developed and validated prospectively in 100 additional patients.
Three algorithms were developed: (1) significant fibrosis (
F≥2 by METAVIR) was identified with high diagnostic performance (>94% accuracy) using APRI as screening test, followed by Fibrotest in APRI non-classified cases and restricting liver biopsy to patients classified F0–F1 by non-invasive tests. (2) A slightly modified algorithm had similar performance when applied to hepatitis C carriers with normal ALT. (3) Identification of cirrhosis (95% accuracy) was achieved using a dedicated algorithm with different cut-off, reducing by 60–70% the liver biopsies needed.
Stepwise combination of non-invasive markers of liver fibrosis improves the diagnostic performance in chronic hepatitis C. Need for liver biopsy is reduced by 50–70% but cannot be completely avoided.
DeepCube is a 3-year Horizon 2020 project that leverages advances in the fields of Artificial Intelligence and Semantic Web to unlock the potential of big Copernicus data. Its goal is to address ...problems of high socio-environmental impact and enhance our understanding of Earth's processes correlated with Climate Change. To achieve this, the project employs mature ICT technologies, integrating them into a scalable, open and interoperable platform that provides solutions for all phases of an Earth Observation based AI pipeline. The Deep- Cube technologies will be demonstrated in five Use Cases.
Affective "Theory of Mind" (ToM) is the specific ability to represent own and others' emotional states and feelings. Previous studies examined affective ToM ability in patients with Huntington's ...disease (HD), using the "Reading the Mind in the Eyes test" (RMET). Results were consistent in showing difficulties in inferring complex mental states from photographs of people even in the early stage of HD. However, there has been no agreement as to whether or not cognitive impairments in HD population might have contributed to poor performance on the RMET test. The aim of the present study was to assess whether the affective ToM ability was impaired in the mild to moderate stages of HD, and whether there was an association between compromised ToM ability and the presence of cognitive impairment. We evaluated ToM by means of RMET and global cognitive functioning by means of the MoCA questionnaire in 15 HD patients and 15 healthy subjects (HS). Both groups were matched for age and level of education. Our study showed that the ability to judge a person's mental states from a picture of their eyes was impaired in HD patients compared to normal population. Indeed, HD subjects gave the 34% of correct responses on RMET, whereas healthy control subjects' percentage of correct responses was 71%. Furthermore, this impairment was not correlated with global cognitive functioning except for the visuospatial task. These results show that RMET might represent a valid instrument to assess affective ToM ability in HD patients in the mild to moderate stages of the disease, independently from their cognitive status. Since it is known that HD patients, in addition to motor symptoms, suffer from cognitive deficits, including memory and executive impairments, it is important to have an instrument, which is not influenced by cognitive abilities. It is possible therefore to use RMET to assess important aspects of HD patients such as their ability to recognize others' emotions and feelings even when patients suffer from cognitive decline.
•Flood modelling in real urban areas is a challenge for differential anisotropic porosity models.•Direction-dependent, cell-based conveyance porosity is not trivial to estimate.•A method is proposed ...to extract conveyance porosity fields from building footprints.•Straightforward application to complex urban layouts provides accurate results.•A Fortran numerical implementation of the proposed method is made available.
In the framework of porosity models for large-scale urban floods, this work presents a method to compute the spatial distribution of the porosity parameters of complex urban areas by analyzing the footprints of buildings and obstacles. Precisely, an algorithm is described that estimates the four parameters required by the differential, dual-porosity formulation we recently presented. In this formulation, beside the common isotropic porosity accounting for the reduced storage volume due to buildings, a cell-based conveyance porosity is introduced in the momentum equations in tensor form to model anisotropic resistances and alterations in the flow direction due to presence of preferential pathways such as streets. A cell-averaged description of the spatial connectivity in the urban medium and of the preferential flow directions is the main ingredient for robust and mesh-independent estimates. To achieve this goal, the algorithm here presented automatically extracts the spatially distributed porosity fields of urban layouts relying only on geometrical information, thus avoiding additional calibration effort. The proposed method is described with the aid of schematic applications and then tested by simulating the flooding of complex urban areas using structured Cartesian grids. A Fortran implementation of the algorithm is made available for free download and use.
This paper presents a novel explicit finite volume scheme for the solution of the two-dimensional Shallow Water Equations (SWEs) with porosity based on the use of an augmented Riemann problem. Bottom ...and porous source terms are treated as non-conservative fluxes by including two additional equations to the porous SWEs. The HLLEM approximate Riemann solver is chosen to compute the fluxes of the non-conservative system of equations in order to ensure robustness, computational efficiency and entropy enforcement also in the presence of significant discontinuities in the porosity field. Moreover, the proposed solver is extended to second order in time and space adopting the ADER time-integration scheme, together with a Total Variation Diminishing (TVD) spatial reconstruction. The model is implemented in CUDA (Compute Unified Device Architecture) language to exploit the computational power of modern Graphic Processing Units. The theoretical and numerical verification of the C-property is achieved also when discontinuities characterize the porosity and bottom fields. The scheme accurately reproduces Riemann problems generated by the presence of porous discontinuities. Numerical tests also confirm that the proposed algorithm retains roughly the same numerical efficiency of an alternative formulation based on a non-augmented Riemann solver, while providing more accurate results.
•Accurate mapping of dam failure-induced floods is crucial to increase population preparedness.•A procedure based on high-resolution shallow water modelling is described.•The adopted GPU shallow ...water model copes with the challenges of the simulated phenomenon.•The procedure is applied to two dams in northern Italy.
This paper presents a procedure based on high-resolution shallow water modelling for assessing dam-failure hypothetical scenarios that can be useful for designing emergency action plans. The capability of accurately predicting the areas flooded by these catastrophic events, both in terms of timing and magnitude, represents indeed a key task for emergency planning. The proposed procedure relies on the adoption of a parallel two-dimensional shallow water numerical model capable of both preventing large computational times and enabling the use of high-resolution meshes without introducing approximations in the set of the governing equations. Criteria for selecting the numerical model, the input data such as bathymetry, and the initial conditions are analysed in detail. The procedure is adopted to model the flooding scenarios induced by the failure of two dams in northern Italy built for irrigation and flood mitigation purposes, respectively.
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