Nonconforming Virtual Element basis functions for space-time Discontinuous Galerkin schemes on unstructured Voronoi meshes

We introduce a new class of Discontinuous Galerkin (DG) methods for solving nonlinear conservation laws on unstructured Voronoi meshes that use a nonconforming Virtual Element basis defined within each polygonal control volume. The basis functions are evaluated as an L2 projection of the virtual basis which remains unknown, along the lines of the Virtual Element Method (VEM). Contrarily to the VEM approach, the new basis functions lead to a nonconforming representation of the solution with discontinuous data across the element boundaries, as typically employed in DG discretizations. To improve the condition number of the resulting mass matrix, an orthogonalization of the full basis is proposed. The discretization in time is carried out following the ADER (Arbitrary order DERivative Riemann problem) methodology, which yields one-step fully discrete schemes that make use of a coupled space-time representation of the numerical solution. The space-time basis functions are constructed as a tensor product of the virtual basis in space and a one-dimensional Lagrange nodal basis in time. The resulting space-time stiffness matrix is stabilized by an extension of the dof-dof stabilization technique adopted in the VEM framework, hence allowing an element-local space-time Galerkin finite element predictor to be evaluated. The novel methods are referred to as VEM-DG schemes, and they are arbitrarily high order accurate in space and time. The new VEM-DG algorithms are rigorously validated against a series of benchmarks in the context of compressible Euler and Navier-Stokes equations. Numerical results are verified with respect to literature reference solutions and compared in terms of accuracy and computational efficiency to those obtained using a standard modal DG scheme with Taylor basis functions. An analysis of the condition number of the mass and space-time stiffness matrix is also forwarded

Dopamine transporter and transmission of psychopathological risk. A review of gene-environment interplay

Research underlines that intergenerational transmission of psychopathological risk results from a complex interplay of genetic and environmental risk factors which predispose child to develop emotionalbehavioral problems. Mechanisms of transmission are poorly understood, but few studies have focused on the role played by dopamine transporter (DAT) gene. This review aims to examine mediating mechanism of DAT genotype-environmental interaction (GxE), DAT genotype-environmental correlation (rGE), and methylation status involved in transmission of psychopathological risk. The review of literature was made through researches in university libraries on paper material, and telematics systems research. Studies have evidenced that DAT is implicated in intergenerational transmission of psychopathological risk. Results are mixed regarding its genetic variants, but mechanisms through which this gene can affect both quality of parenting and child development are partially established. Only few studies have examined methylation mechanisms that can be implicated. Findings suggest to involve an improved focus on DAT genotypes, methylation status associated, and their relationship with environment to better understanding child’s vulnerability and resilience following exposure to contextual risk factors associated with parental psychopathological symptoms

DNA methylation at the DAT promoter and risk for psychopathology. Intergenerational transmission between school-age youths and their parents in a community sample

Background: The effect of gene polymorphisms and promoter methylation, associated with maladaptive developmental outcomes, vary depending on environmental factors (e.g., parental psychopathology). Most studies have focused on 0- to 5-year-old children, adolescents, or adults, whereas there is dearth of research on school-age youths and pre-adolescents. Methods: In a sample of 21 families recruited at schools, we addressed parents' psychopathological symptoms (through SCL-90-R); offspring emotional-behavioral functioning (through CBCL-6-18); dopamine transporter gene (DAT1) for epigenetic status of the 5'-untranslated region (UTR) and for genotype, i.e., variable number of tandem repeats polymorphism at the 3'-UTR. Possible associations were explored between bio-genetic and psychological characteristics within the same individual and between triplets of children, mothers, and fathers. Results: DAT methylation of CpG at positions M1, M6, and M7 in mothers was correlated with maternal (phobic) anxiety, whereas in fathers' position M6 was related to paternal depression, anxiety, hostility, psychoticism, and higher Global Severity Index (GSI). No significant correlations were found between maternal and offspring DAT methylation. Significant correlations were found between fathers' methylation at CpG M1 and children's methylation at CpG M6. Linear regressions showed that mothers and fathers' GSI predicted children's methylation at CpG sites M2, M3, and M6, whereas fathers' GSI predicted children's methylation at CpG sites, particularly M1, M2, and M6. Moreover, offspring methylation of DAT at CpG M2 predicted somatic complaint, internalizing and attention problems; methylation of DAT at CpG M6 predicted withdraw. Conclusion: This study may have important clinical implication for the prevention and treatment of emotional-behavioral difficulties in children, as it adds to previous knowledge about the role of genetic and environmental factors in predicting psychopathological symptoms within non-clinical population

Multispectral Video Fusion for Non-contact Monitoring of Respiratory Rate and Apnea

Continuous monitoring of respiratory activity is desirable in many clinical applications to detect respiratory events. Non-contact monitoring of respiration can be achieved with near- and far-infrared spectrum cameras. However, current technologies are not sufficiently robust to be used in clinical applications. For example, they fail to estimate an accurate respiratory rate (RR) during apnea. We present a novel algorithm based on multispectral data fusion that aims at estimating RR also during apnea. The algorithm independently addresses the RR estimation and apnea detection tasks. Respiratory information is extracted from multiple sources and fed into an RR estimator and an apnea detector whose results are fused into a final respiratory activity estimation. We evaluated the system retrospectively using data from 30 healthy adults who performed diverse controlled breathing tasks while lying supine in a dark room and reproduced central and obstructive apneic events. Combining multiple respiratory information from multispectral cameras improved the root mean square error (RMSE) accuracy of the RR estimation from up to 4.64 monospectral data down to 1.60 breaths/min. The median F1 scores for classifying obstructive (0.75 to 0.86) and central apnea (0.75 to 0.93) also improved. Furthermore, the independent consideration of apnea detection led to a more robust system (RMSE of 4.44 vs. 7.96 breaths/min). Our findings may represent a step towards the use of cameras for vital sign monitoring in medical applications

Integrative Taxonomy of the Bubble Snails (Cephalaspidea, Heterobranchia) Inhabiting a Promising Study Area: The Coastal Sicilian Faro Lake (Southern Italy)

The worldwide diffused bubble snails, Haminoeidae, although characterized by an extreme morphological homogeneity, display the most diverse radiation inside the order Cephalaspidea. This hidden diversity within the family Haminoeidae was recently unraveled by molecular studies, which helped to understand the evolutionary history of this group by clarifying some aspects of its systematics. In fact, the type genus Haminoea W. Turton and Kingston (1830) was proved to be polyphyletic and, consequently, the genus Haminoea sensu stricto was restricted to the Mediterranean, Atlantic and East Pacific species, with the Mediterranean Haminoea hydatis Linnaeus (1758) as the type taxon. However, at the specie rank, many aspects need to be clarified, especially concerning the Mediterranean fauna. Due to low reliability of macro-morphological characters, the minimal quantity of molecular data currently available on Mediterranean specimen adds to the lack of molecular comparison in most reports. Based on such considerations, Haminoea species from an interesting Mediterranean study area, Faro Lake, a Sicilian coastal lake that is considered a hot spot for both alien and endemic marine Heterobranchia, have been studied using an integrative taxonomic approach. Eleven Mediterranean specimens belonging to four Haminoea bubble snails have been collected, identified and compared with samples from other localities, integrating ecological, morphological, anatomical (reproductive apparatus) and molecular data. Based on molecular investigations carried out on three different molecular markers (H3, 16S and COI), the morphological identifications of the species collected in the Faro Lake have been confirmed, and 37 new sequences are provided for future comparisons. Furthermore, results from this integrative systematic study shed light on the phylogenetic relationships occurring in this group of bubble snails that could be useful in identifying valid diagnostic morphological characters. Haminoea hydatis and H. navicula were confirmed to be close to each other, with H. orteai as sister to them and with H. orbignyana as the basal taxon. Given external morphological features are unreliable with species identification in Haminoea genus open questions on the geographical distribution of the species and on their ranges of intraspecific variability have yet to be addressed and further in-depth studies are needed. Finally, the presence of three sympatric Haminoea species, two of which are considered native or long-time naturalized, along with other occasional congeneric species, and the absence of the introduced invasive Haloa japonica, reflects both the resilience and stochastic space-temporal dynamics of Faro Lake. This confirms it as an inexhaustible source of case-studies

A new family of semi-implicit Finite Volume / Virtual Element methods for incompressible flows on unstructured meshes

We introduce a new family of high order accurate semi-implicit schemes for the solution of non-linear hyperbolic partial differential equations on unstructured polygonal meshes. The time discretization is based on a splitting between explicit and implicit terms that may arise either from the multi-scale nature of the governing equations, which involve both slow and fast scales, or in the context of projection methods, where the numerical solution is projected onto the physically meaningful solution manifold. We propose to use a high order finite volume (FV) scheme for the explicit terms, ensuring conservation property and robustness across shock waves, while the virtual element method (VEM) is employed to deal with the discretization of the implicit terms, which typically requires an elliptic problem to be solved. The numerical solution is then transferred via suitable L2 projection operators from the FV to the VEM solution space and vice-versa. High order time accuracy is achieved using the semi-implicit IMEX Runge-Kutta schemes, and the novel schemes are proven to be asymptotic preserving and well-balanced. As representative models, we choose the shallow water equations (SWE), thus handling multiple time scales characterized by a different Froude number, and the incompressible Navier-Stokes equations (INS), which are solved at the aid of a projection method to satisfy the solenoidal constraint of the velocity field. Furthermore, an implicit discretization for the viscous terms is devised for the INS model, which is based on the VEM technique. Consequently, the CFL-type stability condition on the maximum admissible time step is based only on the fluid velocity and not on the celerity nor on the viscous eigenvalues. A large suite of test cases demonstrates the accuracy and the capabilities of the new family of schemes to solve relevant benchmarks in the field of incompressible fluids

Trajectory Discrimination and Peripersonal Space Perception in Newborns

The ability to discriminate the trajectories of moving objects is highly adaptive and fundamental for physical and social interactions. Therefore, we could reasonably expect sensitivity to different trajectories already at birth, as a precursor of later communicative and defensive abilities. To investigate this possibility, we measured newborns\u2019 looking behavior to evaluate their ability to discriminate between visual stimuli depicting motion along different trajectories happening within the space surrounding their body. Differently from previous studies, we did not take into account defensive reactions, which may not be elicited by impending collision as newborns might not categorize approaching stimuli as possible dangers. In two experiments, we showed that newborns display a spontaneous visual preference for trajectories directed toward their body. We found this visual preference when visual stimuli depicted motion in opposite directions (approaching vs. receding) as well as when they both moved toward the peripersonal space and differed only in their specific target (i.e., the body vs. the space around it). These findings suggest that at birth human infants seem to be already equipped with visual mechanisms predisposing them to perceive their presence in the environment and to adaptively focus their attention on the peripersonal space and their bodily self

Newborns Are Sensitive to Impending Collision Within Their Peripersonal Space

Immediately after birth, newborns are introduced within a highly stimulating environment, where many objects move close to them. It would therefore be adaptive for infants to pay more attention to objects that move towards them - on a colliding pathway - and could therefore come into contact and interact with them. The present study aimed at understanding if newborns are able to discriminate between colliding vs. noncolliding trajectories. To address this issue, we measured the looking behaviour of newborns who were presented with videos of different pairings of three events: approaching objects along a colliding course, approaching objects along a non-colliding trajectory, and receding objects. Results outlined that newborns preferred looking at the approaching and colliding movement than at both the receding and the approaching but non-colliding movements. Data also suggest the possible occurrence of a configural effect when two colliding events are displayed simultaneously. Furthermore newborns appeared to look longer at movements directed towards the Peripersonal Space than at those directed away from it

Kinetic Modelling of Epidemic Dynamics: Social Contacts, Control with Uncertain Data, and Multiscale Spatial Dynamics

In this survey we report some recent results in the mathematical modelling of epidemic phenomena through the use of kinetic equations. We initially consider models of interaction between agents in which social characteristics play a key role in the spread of an epidemic, such as the age of individuals, the number of social contacts, and their economic wealth. Subsequently, for such models, we discuss the possibility of containing the epidemic through an appropriate optimal control formulation based on the policy maker’s perception of the progress of the epidemic. The role of uncertainty in the data is also discussed and addressed. Finally, the kinetic modelling is extended to spatially dependent settings using multiscale transport models that can characterize the impact of movement dynamics on epidemic advancement on both one-dimensional networks and realistic two-dimensional geographic settings