Evolution of the Stellar Mass--Metallicity Relation - I: Galaxies in the z~0.4 Cluster Cl0024

We present the stellar mass-stellar metallicity relationship (MZR) in the Cl0024+1654 galaxy cluster at z~0.4 using full spectrum stellar population synthesis modeling of individual quiescent galaxies. The lower limit of our stellar mass range is $M_*=10^{9.7}M_\odot$, the lowest galaxy mass at which individual stellar metallicity has been measured beyond the local universe. We report a detection of an evolution of the stellar MZR with observed redshift at $0.037\pm0.007$ dex per Gyr, consistent with the predictions from hydrodynamical simulations. Additionally, we find that the evolution of the stellar MZR with observed redshift can be explained by an evolution of the stellar MZR with their formation time, i.e., when the single stellar population (SSP)-equivalent ages of galaxies are taken into account. This behavior is consistent with stars forming out of gas that also has an MZR with a normalization that decreases with redshift. Lastly, we find that over the observed mass range, the MZR can be described by a linear function with a shallow slope, ($[Fe/H] \propto (0.16 \pm 0.03) \log M_*$). The slope suggests that galaxy feedback, in terms of mass-loading factor, might be mass-independent over the observed mass and redshift range.Comment: 22 pages, 10 figures. Accepted for publication in Ap

IoT Sentinel: Automated Device-Type Identification for Security Enforcement in IoT

With the rapid growth of the Internet-of-Things (IoT), concerns about the security of IoT devices have become prominent. Several vendors are producing IP-connected devices for home and small office networks that often suffer from flawed security designs and implementations. They also tend to lack mechanisms for firmware updates or patches that can help eliminate security vulnerabilities. Securing networks where the presence of such vulnerable devices is given, requires a brownfield approach: applying necessary protection measures within the network so that potentially vulnerable devices can coexist without endangering the security of other devices in the same network. In this paper, we present IOT SENTINEL, a system capable of automatically identifying the types of devices being connected to an IoT network and enabling enforcement of rules for constraining the communications of vulnerable devices so as to minimize damage resulting from their compromise. We show that IOT SENTINEL is effective in identifying device types and has minimal performance overhead

Diagnostic odyssey for rare diseases: exploration of potential indicators

To explore whether an accurate, robust and cost-effective method can be developed for the routine measurement of the rare diseases diagnostic odysseys to enable the impact of interventions and policies, such as the 2013 UK Strategy for Rare Diseases, to be evaluated

Cavity Light Bullets: 3D Localized Structures in a Nonlinear Optical Resonator

We consider the paraxial model for a nonlinear resonator with a saturable absorber beyond the mean-field limit and develop a method to study the modulational instabilities leading to pattern formation in all three spatial dimensions. For achievable parametric domains we observe total radiation confinement and the formation of 3D localised bright structures. At difference from freely propagating light bullets, here the self-organization proceeds from the resonator feedback, combined with diffraction and nonlinearity. Such "cavity" light bullets can be independently excited and erased by appropriate pulses, and once created, they endlessly travel the cavity roundtrip. Also, the pulses can shift in the transverse direction, following external field gradients.Comment: 4 pages, 3 figures, simulations files available at http://www.ba.infn.it/~maggipin/PRLmovies.htm, submitted to Physical Review Letters on 24 March 200

On the monotonicity of scalar curvature in classical and quantum information geometry

We study the statistical monotonicity of the scalar curvature for the alpha-geometries on the simplex of probability vectors. From the results obtained and from numerical data we are led to some conjectures about quantum alpha-geometries and Wigner-Yanase-Dyson information. Finally we show that this last conjecture implies the truth of the Petz conjecture about the monotonicity of the scalar curvature of the Bogoliubov-Kubo-Mori monotone metric.Comment: 20 pages, 2 .eps figures; (v2) section 2 rewritten, typos correcte

Redundant variables and Granger causality

We discuss the use of multivariate Granger causality in presence of redundant variables: the application of the standard analysis, in this case, leads to under-estimation of causalities. Using the un-normalized version of the causality index, we quantitatively develop the notions of redundancy and synergy in the frame of causality and propose two approaches to group redundant variables: (i) for a given target, the remaining variables are grouped so as to maximize the total causality and (ii) the whole set of variables is partitioned to maximize the sum of the causalities between subsets. We show the application to a real neurological experiment, aiming to a deeper understanding of the physiological basis of abnormal neuronal oscillations in the migraine brain. The outcome by our approach reveals the change in the informational pattern due to repetitive transcranial magnetic stimulations.Comment: 4 pages, 5 figures. Accepted for publication in Physical Review

Stochastic Turing patterns in the Brusselator model

A stochastic version of the Brusselator model is proposed and studied via the system size expansion. The mean-field equations are derived and shown to yield to organized Turing patterns within a specific parameters region. When determining the Turing condition for instability, we pay particular attention to the role of cross diffusive terms, often neglected in the heuristic derivation of reaction diffusion schemes. Stochastic fluctuations are shown to give rise to spatially ordered solutions, sharing the same quantitative characteristic of the mean-field based Turing scenario, in term of excited wavelengths. Interestingly, the region of parameter yielding to the stochastic self-organization is wider than that determined via the conventional Turing approach, suggesting that the condition for spatial order to appear can be less stringent than customarily believed.Comment: modified version submitted to Phys Rev. E. 5. 3 Figures (5 panels) adde

The disordered-free-moment phase: a low-field disordered state in spin-gap antiferromagnets with site dilution

Site dilution of spin-gapped antiferromagnets leads to localized free moments, which can order antiferromagnetically in two and higher dimensions. Here we show how a weak magnetic field drives this order-by-disorder state into a novel disordered-free-moment phase, characterized by the formation of local singlets between neighboring moments and by localized moments aligned antiparallel to the field. This disordered phase is characterized by the absence of a gap, as it is the case in a Bose glass. The associated field-driven quantum phase transition is consistent with the universality of a superfluid-to-Bose-glass transition. The robustness of the disordered-free-moment phase and its prominent features, in particular a series of pseudo-plateaus in the magnetization curve, makes it accessible and relevant to experiments.Comment: 4 pages, 4 figure

Flow Field Measurements in a Large Controlled Ventilated Room

A large-scale test room, which represents a Test Control Room facilities in scale 1:1, has been recently developed in order to evaluate the internal flow filed induced by the ventilation system. Due to its crucial relevance in numerous technical applications, rooms ventilation efficiency has been subject of several scientific investigations considering also the restricted requirements that such devices should satisfy in terms of microbiology, particulate concentration and pathogen diffusion (Covid-19). Such a large-scale test room with an internal dimension of 6x6x3 m (corresponding to an internal volume of 108 m3) has been equipped with four inlets and twelve exhaust terminal grids, parts of the ventilation system entirely customary designed. In order to assess effects of different air flow rates, induced by the ventilation system, on the internal flow distribution, a relevant number of three dimensional velocity measurements has been performed, under isothermal conditions, by using a fiber optic Laser Doppler Velocimetry. Consistently with the survived literature, two different inlet flow rates have been considered, in particular 15 and 30 Air Change per Hour (ACH) respectively corresponding to 0.45 and 0.90 m3/s. The whole campaign of measurements has been performed totally in 690 points for a total of 4140 single velocity components acquired