Self-organization practices in cities: discussing the transformative potential

In a growing number of small and large cities across Europe, citizens are engaging and mobilizing to demonstrate their ability in creating innovative solutions for important social and spatial challenges. We are witnessing a different set of micro-practices that are transforming cities ‘from below’, thus questioning not only the relation between active citizenship and the State (Uitermark, 2015) but also forms of urban activation themselves. In this paper we examine the politics of urban self organization with a particular focus on the implications for local governments and the transformative potential of these practices for local communities

Differential neural dynamics underling pragmatic and semantic affordance processing in macaque ventral premotor cortex

Premotor neurons play a fundamental role in transforming physical properties of observed objects, such as size and shape, into motor plans for grasping them, hence contributing to "pragmatic" affordance processing. Premotor neurons can also contribute to "semantic" affordance processing, as they can discharge differently even to pragmatically identical objects depending on their behavioural relevance for the observer (i.e. edible or inedible objects). Here, we compared the response of monkey ventral premotor area F5 neurons tested during pragmatic (PT) or semantic (ST) visuomotor tasks. Object presentation responses in ST showed shorter latency and lower object selectivity than in PT. Furthermore, we found a difference between a transient representation of semantic affordances and a sustained representation of pragmatic affordances at both the single neuron and population level. Indeed, responses in ST returned to baseline within 0.5 s whereas in PT they showed the typical sustained visual-to-motor activity during Go trials. In contrast, during No-go trials, the time course of pragmatic and semantic information processing was similar. These findings suggest that premotor cortex generates different dynamics depending on pragmatic and semantic information provided by the context in which the to-be-grasped object is presented

Temperature Effects on Soft Error Rate Due to Atmospheric Neutrons on 28 nm FPGAs

In ambiti come l'avionica e l'automotive e' difficile garantire un'alta affidabilita' dell'elettronica per la presenza di radiazione. In tale lavoro sperimentale su FPGA si vuole tracciare una relazione fra il tasso di Single Event Upset dovuti a neutroni atmosferici nelle memorie SRAM e la frequenza di funzionamento del circuito. I risultati mostrano che e' difficile avere una spiegazione teorica del fenomeno e che il tasso di SEU e' legato più alla temperatura del ciruito che alla frequenza.ope

Modified Gravitational Waves Across Galaxies from Macroscopic Gravity

We analyze the propagation of gravitational waves in a medium containing bounded subsystems ("molecules"), able to induce significant Macroscopic Gravity effects. We establish a precise constitutive relation between the average quadrupole and the amplitudes of a vacuum gravitational wave, via the geodesic deviation equation. Then we determine the modified equation for the wave inside the medium and the associated dispersion relation. A phenomenological analysis shows that anomalous polarizations of the wave emerge with an appreciable experimental detectability if the medium is identified with a typical galaxy. Both the modified dispersion relation (wave velocity less than the speed of light) and anomalous oscillations modes could be detectable by the incoming LISA or pulsar timing arrays experiments, having the appropriate size to see the concerned wavelengths (larger than the molecular size) and the appropriate sensitivity to detect the expected deviation from vacuum General Relativity.Comment: 10 pages, comments are welcom

Direct Measurement of Competing Quantum Effects on the Kinetic Energy of Heavy Water upon Melting

Even at room temperature, quantum mechanics plays a major role in determining the quantitative behaviour of light nuclei, changing significantly the values of physical properties such as the heat capacity. However, other observables appear to be only weakly affected by nuclear quantum effects (NQEs): for instance, the melting temperatures of light and heavy water differ by less than 4 K. Recent theoretical work has attributed this to a competition between intra and inter molecular NQEs, which can be separated by computing the anisotropy of the quantum kinetic energy tensor. The principal values of this tensor change in opposite directions when ice melts, leading to a very small net quantum mechanical effect on the melting point. This paper presents the first direct experimental observation of this phenomenon, achieved by measuring the deuterium momentum distributions n(p) in heavy water and ice using Deep Inelastic Neutron Scattering (DINS), and resolving their anisotropy. Results from the experiments, supplemented by a theoretical analysis, show that the anisotropy of the quantum kinetic energy tensor can also be captured for heavier atoms such as oxygen

Artificial vs biological meshes: can in vitro cellular responses predict the outcome in patients?

Synthetic and biological matrices for abdominal wall repair have been developed and commercialized in recent years. Biological meshes have been proposed as an alternative when synthetic implants are not indicated, as in the case of contaminated surgical field and may present fewer complications such as chronic pain and visceral adhesions after hernia repair. However, their use is still debated, due to high cost to benefit ratio. Moreover, knowledge of the molecular pathways activated in the different types of cells by their use is still lacking. This study aimed to investigate the molecular processes activated by fibroblasts during their interaction with different types of biological and synthetic matrices, comparing the fibroblast-matrix interactions morphologically, monitoring cell proliferation and the expression of genes involved in the deposition and reabsorption of collagen, as well as some cytokines and markers of differentiation into myofibroblasts. We found that fibroblasts grew differently on the different biological meshes. Few fibroblasts grew on the synthetic mesh, impairing gene expression analysis. Fibroblasts on biological meshes induced specific metalloproteinases and reduced expression of collagen genes compared to control cells. Expression of markers for myofibroblast differentiation was also reduced. We found limited differences in gene expression programs among the different biological meshes

How Gaussian can our Universe be?

Gravity is a non-linear theory, and hence, barring cancellations, the initial super-horizon perturbations produced by inflation must contain some minimum amount of mode coupling, or primordial non-Gaussianity. In single-field slow-roll models, where this lower bound is saturated, non-Gaussianity is controlled by two observables: the tensor-to-scalar ratio, which is uncertain by more than fifty orders of magnitude; and the scalar spectral index, or tilt, which is relatively well measured. It is well known that to leading and next-to-leading order in derivatives, the contributions proportional to the tilt disappear from any local observable, and suspicion has been raised that this might happen to all orders, allowing for an arbitrarily low amount of primordial non-Gaussianity. Employing Conformal Fermi Coordinates, we show explicitly that this is not the case. Instead, a contribution of order the tilt appears in local observables. In summary, the floor of physical primordial non-Gaussianity in our Universe has a squeezed-limit scaling of $k_\ell^2/k_s^2$, similar to equilateral and orthogonal shapes, and a dimensionless amplitude of order $0.1\times(n_\mathrm{s}-1)$.Comment: 26 + 18 pages, 2 figures. References added and minor typos corrected. Matches published versio

Transitional Dynamics Towards Sustainability: Reconsidering the EKC Hypothesis

The Environmental Kuznets Curve (EKC) hypothesis is one of the most debated economic issues. Despite its fascinating appeal for any policy maker, neither theoretical nor certain empirical evidence has been found to clean up all doubt. The aim of this paper is to present an economy where environmental quality and polluting emissions do enter the maximisation problem, and provide a transitional dynamics analysis to pursue a new different version of the EKC, depending on the level of development finally achieved.Environmental Quality, Endogenous Economic Growth, Sustainable Development