On a class of rational matrices and interpolating polynomials related to the discrete Laplace operator

Let \dlap be the discrete Laplace operator acting on functions (or rational matrices) $f:\mathbf{Q}_L\to\mathbb{Q}$, where $\mathbf{Q}_L$ is the two dimensional lattice of size $L$ embedded in $\mathbb{Z}_2$. Consider a rational $L\times L$ matrix $\mathcal{H}$, whose inner entries $\mathcal{H}_{ij}$ satisfy \dlap\mathcal{H}_{ij}=0. The matrix $\mathcal{H}$ is thus the classical finite difference five-points approximation of the Laplace operator in two variables. We give a constructive proof that $\mathcal{H}$ is the restriction to $\mathbf{Q}_L$ of a discrete harmonic polynomial in two variables for any $L>2$. This result proves a conjecture formulated in the context of deterministic fixed-energy sandpile models in statistical mechanics.Comment: 18 pag, submitted to "Note di Matematica

Agent, action and agent's awareness. A conceptual clarification of our experience

In this paper I propose two genuine philosophical approaches to action and I compare the different positions about this topic. I attempt to show that Heidegger’s elaboration about the “worldlessness of world”, about “poverty in world of animal” and about the “world-formation of Dasein” can bring to mind Gallagher&Zahavi’s distinction about “oriented-towards-something movements”, “action”, and “action with sense of agency”. In this sense I try to reflect about act, action, agent and about the agent’s awareness to be an agent towards a phenomenology of action, towards a phenomenological clarification of our experience. In the first part I propose some philosophical elements about phenomenology of action showing how it is difficult to identify two or more experiences “as the same experiences”. In the second part I recall very briefly the main line of Gallagher&Zahavi perspective that we can find principally in “The Phenomenological Mind” where they try to explain the different aspects of movement and action proposing some reflections about agency. In the third part I expose Heidegger’s position that we can find in the “The Fundamental Concepts of Metaphysics”. In the fourth part, I present the synergetic attempt of comparison between Heidegger thought and Gallagher&Zahavi perspective

On a class of rational matrices and interpolating polynomials related to the discrete Laplace operator

Let \dlap be the discrete Laplace operator acting on functions(or rational matrices) $f:\mathbf{Q}_L\rightarrow\mathbb{Q}$,where $\mathbf{Q}_L$ is the two dimensional lattice of size $L$embedded in $\mathbb{Z}_2$. Consider a rational $L\times L$ matrix $\mathcal{H}$, whose inner entries $\mathcal{H}_{ij}$ satisfy \dlap\mathcal{H}_{ij}=0. The matrix $\mathcal{H}$ is thus theclassical finite difference five-points approximation of theLaplace operator in two variables. We give a constructive proofthat $\mathcal{H}$ is the restriction to $\mathbf{Q}_L$ of adiscrete harmonic polynomial in two variables for any L>2. Thisresult proves a conjecture formulated in the context ofdeterministic fixed-energy sandpile models in statisticalmechanics

Metric Features of a Dipolar Model

The lattice spin model, with nearest neighbor ferromagnetic exchange and long range dipolar interaction, is studied by the method of time series for observables based on cluster configurations and associated partitions, such as Shannon entropy, Hamming and Rohlin distances. Previous results based on the two peaks shape of the specific heat, suggested the existence of two possible transitions. By the analysis of the Shannon entropy we are able to prove that the first one is a true phase transition corresponding to a particular melting process of oriented domains, where colored noise is present almost independently of true fractality. The second one is not a real transition and it may be ascribed to a smooth balancing between two geometrical effects: a progressive fragmentation of the big clusters (possibly creating fractals), and the slow onset of a small clusters chaotic phase. Comparison with the nearest neighbor Ising ferromagnetic system points out a substantial difference in the cluster geometrical properties of the two models and in their critical behavior.Comment: 20 pages, 15 figures, submitted to JPhys

Mechanical Processing of Hermetia illucens Larvae and Bombyx mori Pupae Produces Oils with Antimicrobial Activity

The aim of this work was to develop processing methods that safeguard the quality and antimicrobial properties of H. illucens and B. mori oils. We adopted a vegetable diet for both insects: leftover vegetables and fruit for H. illucens and mulberry leaves for B. mori. First, alternative techniques to obtain a good oil extraction yield from the dried biomass of H. illucens larvae were tested. Traditional pressing resulted to be the best system to maximize the oil yield and it was successfully applied to B. mori pupae. Oil quality resulted comparable to that obtained with other extraction methods described in the literature. In the case of B. mori pupae, different treatments and preservation periods were investigated to evaluate their influence on the oil composition and quality. Interestingly, agar diffusion assays demonstrated the sensitivity of Gram-positive Bacillus subtilis and Staphylococcus aureus to H. illucens and B. mori derived oils, whereas the growth of Gram-negative Pseudomonas aeruginosa and Escherichia coli was not affected. This study confirms that fat and other active compounds of the oil extracted by hot pressing could represent effective antimicrobials against bacteria, a relevant result if we consider that they are by-products of the protein extraction process in the feed industry

Application of a general discrete adjoint method for draft tube optimization

ABSTRACT: Automatic optimization is becoming increasingly important in turbomachinery design to improve the performance of machine components and Evolutionary Algorithms (EAs) play a very important role in this task. The main drawback of EAs is the large number of evaluations that are required to obtain an "optimal" result. Consequently, in order to keep the computational time in an affordable frame for design purposes, either the mesh size has to be limited, thus reducing the resolution of the flow phenomena, or the number of free parameters must be kept small. Adjoint optimization does not suffer from these restrictions, i.e. the optimization time is not affected by the number of parameters. The computational effort for the adjoint method scales only with the grid size and is usually in the range of two times the CFD simulation alone. In this paper, a discrete adjoint method based on a coupled pressure based RANS solver is presented and applied to draft tube optimization. The adjoint solver is general and can therefore deal with any turbulence model supported by the CFD solver as well as any boundary condition, including mixing planes and mesh interfaces needed for multi-stage simulations. Furthermore, there is no restriction on the choice of objective function. The adjoint method is first applied to a baseline draft tube geometry and then again to its EA optimized geometry where the objective function was the minimization of losses in the draft tube. To reduce the complexity for this proof of concept but still including multiple operating points in the optimization, only peak efficiency and full-load were optimized simultaneously. The adjoint optimization can significantly improve the draft tube performance in both cases (baseline and EA optimization). The interplay between local and global optimization seems to be a promising strategy to find optimal geometries for multi-operating point/multi-objective optimization and will be further investigated in subsequent research

A soil fungus confers plant resistance against a phytophagous insect by disrupting the symbiotic role of its gut microbiota

Plants generate energy flows through natural food webs, driven by competition for resources among organisms, which are part of a complex network of multitrophic interactions. Here, we demonstrate that the interaction between tomato plants and a phytophagous insect is driven by a hidden interplay between their respective microbiotas. Tomato plants colonized by the soil fungus Trichoderma afroharzianum, a beneficial microorganism widely used in agriculture as a biocontrol agent, negatively affects the development and survival of the lepidopteran pest Spodoptera littoralis by altering the larval gut microbiota and its nutritional support to the host. Indeed, experiments aimed to restore the functional microbial community in the gut allow a complete rescue. Our results shed light on a novel role played by a soil microorganism in the modulation of plant-insect interaction, setting the stage for a more comprehensive analysis of the impact that biocontrol agents may have on ecological sustainability of agricultural systems

How do i know what you are going to do ? a multi-level action understanding model for social interactions

This work focuses on three topics: the social value of motor cognition (i.e. experimental studies in human and non-human primates showing that the parieto-frontal mirror circuit plays a crucial role in action understanding before and below mindreading abilities); motor encoding of action anomalies in individuals with autism spectrum disorder that may explain – to a degree – their limited social abilities; failure of social agreement resulting in criminal actions that may be clarified thanks to neuroscience data in forensic psychiatric evaluation. Describing the role of experimental data – notably the functional role of cortical motor system – in clarifying social experience, this work reverses also the way in which we consider ourselves as agents in social interactions. This work focuses on behaviours, brain and concepts. This work draws a synergetic view integrating conceptual, experimental, clinical and forensic perspectives. This work, for saving phenomena, forces the categories

Agent, action and agent’s awareness. A conceptual clari cation of our experience

In this paper I propose two genuine philosophical approaches to action and I compare the different positions about this topic. I attempt to show that Heidegger’s elaboration about the “worldlessness of world”, about “poverty in world of animal” and about the “world-formation of Dasein” can bring to mind Gallagher&Zahavi’s distinction about “oriented-towards-something movements”, “action”, and “action with sense of agency”. In this sense I try to reflect about act, action, agent and about the agent’s awareness to be an agent towards a phenomenology of action, towards a phenomenological clarification of our experience. In the first part I propose some philosophical elements about phenomenology of action showing how it is difficult to identify two or more experiences “as the same experiences”. In the second part I recall very briefly the main line of Gallagher&Zahavi perspective that we can find principally in “The Phenomenological Mind” where they try to explain the different aspects of movement and action proposing some reflections about agency. In the third part I expose Heidegger’s position that we can find in the “The Fundamental Concepts of Metaphysics”. In the fourth part, I present the synergetic attempt of comparison between Heidegger thought and Gallagher&Zahavi perspective

The motor way: Clinical implications of understanding and shaping actions with the motor system in autism and drug addiction

To understand others' minds is crucial for survival; however, it is quite puzzling how access to others' minds can be-to some extent-direct and not necessarily mediated by conceptual reasoning. Recent advances in neuroscience have led to hypothesize a role for motor circuits not only in controlling the elementary physical features of movement (e.g., force, direction, and amplitude), but also in understanding and shaping human behavior. The concept of "motor cognition" refers to these aspects, and neurophysiological, neuroimaging, and behavioral studies in human and nonhuman primates support this view. From a clinical perspective, motor cognition represents a challenge in several domains. A thorough investigation of the neural mechanisms mediating motor action/intention understanding and automatized/compulsive behaviors seems to be a promising way to tackle a range of neurodevelopmental and drug-related disorders. On the one hand, anomalies in motor cognition may have cascade effects on social functioning in individuals with autism spectrum disorder (ASD); on the other, motor cognition may help explain the pathophysiology of drug-seeking and drug-taking behaviors in the most severe phase of drug addiction (i.e.,\ua0see drug dependence, motor low-order cue reactivity). This may represent\ua0a promising approach that could improve the efficacy of rehabilitative interventions. The only way to shed light on multifactorial disorders such as ASD and drug addiction is through the investigation of their multiple factors. This motor way can promote new theoretical and experimental perspectives that would help bridge the gap between the basic neuroscience approach and clinical practice