APPLICATIONS OF THE INFRARED THERMOGRAPHY TO THE ASSESSMENT OF HISTORIC BUILDINGS: A CASE STUDY IN PISA

Measuring the thermal response of materials in building assessment has a wide range of applications concerning not only the thermophysical aspects, but also the structural ones. The last topic is particularly interesting in the context of historic buildings, where the modern tools for surface temperature measurement are capable of providing many useful information: the masonry texture and the materials detection under the plaster are the fundamentals for the evaluation of the structural behavior and for the selection of the strengthening and restoration criteria. In this regard, the full-field, contactless and real time investigation makes the infrared thermography indispensable. The thermographic technique is taken here into consideration in an emblematic case study

GPUs Based Material Point Method for Compressible Flows

Particle-In-Cell (PIC) methods such as the Material Point Method (MPM) can be cast in formulations suitable to the requirements of data locality and fine-grained parallelism of modern hardware accelerators such as Graphics Processing Units (GPUs). While continuum mechanics simulations have already shown the capabilities of MPM on a wide range of phenomena, the use of the method in compressible gas dynamics is less frequent. This contribution aims to show the potential of a GPU-based MPM parallel implementation for compressible fluid dynamics, as well as to assess the reliability of this approach in reproducing supersonic gas flows against solid obstacles. The results in the paper represent a stepping stone towards a highly parallel, Multi-GPU, MPM-base solver for M ach > 1 Fluid-Structure Interaction problems

Speed and entropy of an interacting continuous time quantum walk

We present some dynamic and entropic considerations about the evolution of a continuous time quantum walk implementing the clock of an autonomous machine. On a simple model, we study in quite explicit terms the Lindblad evolution of the clocked subsystem, relating the evolution of its entropy to the spreading of the wave packet of the clock. We explore possible ways of reducing the generation of entropy in the clocked subsystem, as it amounts to a deficit in the probability of finding the target state of the computation. We are thus lead to examine the benefits of abandoning some classical prejudice about how a clocking mechanism should operate.Comment: 25 pages, 14 figure

Grover's algorithm on a Feynman computer

We present an implementation of Grover's algorithm in the framework of Feynman's cursor model of a quantum computer. The cursor degrees of freedom act as a quantum clocking mechanism, and allow Grover's algorithm to be performed using a single, time-independent Hamiltonian. We examine issues of locality and resource usage in implementing such a Hamiltonian. In the familiar language of Heisenberg spin-spin coupling, the clocking mechanism appears as an excitation of a basically linear chain of spins, with occasional controlled jumps that allow for motion on a planar graph: in this sense our model implements the idea of "timing" a quantum algorithm using a continuous-time random walk. In this context we examine some consequences of the entanglement between the states of the input/output register and the states of the quantum clock

Neutron star radius-To-mass ratio from partial accretion disk occultation as measured through fe kα line profiles

We present a new method to measure the radius-To-mass ratio (R/M) of weakly magnetic, disk-Accreting neutron stars by exploiting the occultation of parts of the inner disk by the star itself. This occultation imprints characteristic features on the X-ray line profile that are unique and are expected to be present in low-mass X-ray binary systems seen under inclinations higher than ∼65°. We analyze a Nuclear Spectroscopic Telescope Array observation of a good candidate system, 4U 1636-53, and find that X-ray spectra from current instrumentation are unlikely to single out the occultation features owing to insufficient signal-To-noise. Based on an extensive set of simulations we show that large-Area X-ray detectors of the future generation could measure R/M to ∼2 ÷ 3% precision over a range of inclinations. Such is the precision in radius determination required to derive tight constraints on the equation of state of ultradense matter and it represents the goal that other methods also aim to achieve in the future

Identification of Cdk8 and Cdkn2d as New Prame-Target Genes in 2C-like Embryonic Stem Cells

Embryonic stem cells (ESCs) present a characteristic pluripotency heterogeneity correspondent to specific metastates. We recently demonstrated that retinoic acid (RA) induces an increase in a specific 2C-like metastate marked by target genes specific to the two-cell embryo stage in preimplantation. Prame (Preferentially expressed antigen in melanoma) is one of the principal actors of the pluripotency stage with a specific role in RA responsiveness. Additionally, PRAME is overexpressed in a variety of cancers, but its molecular functions are poorly understood. To further investigate Prame’s downstream targets, we used a chromatin immunoprecipitation sequencing (ChIP-seq) assay in RA-enriched 2C-like metastates and identified two specific target genes, Cdk8 and Cdkn2d, bound by Prame. These two targets, involved in cancer dedifferentiation and pluripotency, have been further validated in RA-resistant ESCs. Here, we observed for the first time that Prame controls the Cdk8 and Cdkn2d genes in ESCs after RA treatment, shedding light on the regulatory network behind the establishment of naïve pluripotency

HAT-P-55b: A Hot Jupiter Transiting a Sun-like Star

We report the discovery of a new transiting extrasolar planet, HAT-P-55b. The planet orbits a V = 13.207 +/- 0.039 sun-like star with a mass of 1.013 +/- 0.037 solar masses, a radius of 1.011 +/- 0.036 solar radii and a metallicity of -0.03 +/- 0.08. The planet itself is a typical hot Jupiter with a period of 3.5852467 +/- 0.0000064 days, a mass of 0.582 +/- 0.056 Jupiter masses and a radius of 1.182 +/- 0.055 Jupiter radii. This discovery adds to the increasing sample of transiting planets with measured bulk densities, which is needed to put constraints on models of planetary structure and formation theories.Comment: 7 pages, 4 figures, accepted for publication in PAS

Transport regimes of cold gases in a two-dimensional anisotropic disorder

We numerically study the dynamics of cold atoms in a two-dimensional disordered potential. We consider an anisotropic speckle potential and focus on the classical regime, which is relevant to some recent experiments. First, we study the behavior of particles with a fixed energy and identify different transport regimes. For low energy, the particles are classically localized due to the absence of a percolating cluster. For high energy, the particles undergo normal diffusion and we show that the diffusion constants scale algebraically with the particle energy, with an anisotropy factor which significantly differs from that of the disordered potential. For intermediate energy, we find a transient sub-diffusive regime, which is relevant to the time scale of typical experiments. Second, we study the behavior of a cold-atomic gas with an arbitrary energy distribution, using the above results as a groundwork. We show that the density profile of the atomic cloud in the diffusion regime is strongly peaked and, in particular, that it is not Gaussian. Its behavior at large distances allows us to extract the energy-dependent diffusion constants from experimental density distributions. For a thermal cloud released into the disordered potential, we show that our numerical predictions are in agreement with experimental findings. Not only does this work give insights to recent experimental results, but it may also serve interpretation of future experiments searching for deviation from classical diffusion and traces of Anderson localization.Comment: 19 pages, 16 figure

Climatic changes and human impact on coastal areas of Sardinia: the example of the Mistras-Cabras barrier-lagoon system (Central-Western Sardinia)

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VEGFR1 signaling in retinal angiogenesis and microinflammation

Five vascular endothelial growth factor receptor (VEGFR) ligands (VEGF-A, -B, –C, -D, and placental growth factor [PlGF]) constitute the VEGF family. VEGF-A binds to VEGF receptors 1 and 2 (VEGFR1/2), whereas VEGF-B and PlGF only bind VEGFR1. Although much research has been conducted on VEGFR2 to elucidate its key role in retinal diseases, recent efforts have shown the importance and involvement of VEGFR1 and its family of ligands in angiogenesis, vascular permeability, and microinflammatory cascades within the retina. Expression of VEGFR1 depends on the microenvironment, is differentially regulated under hypoxic and inflammatory conditions, and it has been detected in retinal and choroidal endothelial cells, pericytes, retinal and choroidal mononuclear phagocytes (including microglia), Müller cells, photoreceptor cells, and the retinal pigment epithelium. Whilst the VEGF-A decoy function of VEGFR1 is well established, consequences of its direct signaling are less clear. VEGFR1 activation can affect vascular permeability and induce macrophage and microglia production of proinflammatory and proangiogenic mediators. However the ability of the VEGFR1 ligands (VEGF-A, PlGF, and VEGF-B) to compete against each other for receptor binding and to heterodimerize complicates our understanding of the relative contribution of VEGFR1 signaling alone toward the pathologic processes seen in diabetic retinopathy, retinal vascular occlusions, retinopathy of prematurity, and age-related macular degeneration. Clinically, anti-VEGF drugs have proven transformational in these pathologies and their impact on modulation of VEGFR1 signaling is still an opportunity-rich field for further research