2,468 research outputs found

    Technical change, non-tariff barriers, and the development of the Italian locomotive industry, 1850–1913

    Get PDF
    The locomotive industry was one of the relatively sophisticated “high tech” sectors in which Italy, a late industrializer, was successful before 1913. Using technical data on the performance of different vintages of locomotives, we construct a new industry-level index of technical change. We also study the impact of different policy instruments (import duties, non-tariff trade barriers, and other discretionary interventions) in shaping the development of the industry. Our reassessment reveals not only the sound technological performance of Italian locomotives and successful industry growth, but also the critical role played by non-tariff barriers for the development of the industry

    Daclizumab-induced encephalitis in multiple sclerosis

    Get PDF

    Response of the multiple sclerosis community to COVID-19

    Get PDF

    Coordination between leaf and root traits in Mediterranean coastal dune plants

    Get PDF
    Plant trait-based functional spectra are crucial to assess ecosystem functions and services. Whilst most research has focused on aboveground vegetative traits (leaf economic spectrum, LES), contrasting evidence on any coordination between the LES and root economic spectrum (RES) has been reported. Studying spectra variation along environmental gradients and accounting for species' phylogenetic relatedness may help to elucidate the strength of coordination between above- and belowground trait variation.center dot We focused on leaf and root traits of 39 species sampled in three distinct habitats (front, back and slack) along a shoreline-inland gradient on coastal dunes. We tested, within a phylogenetic comparative framework, for the presence of the LES and RES, for any coordination between these spectra, and explored their relation to variation in ecological strategies along this gradient.center dot In each habitat, three-quarters of trait variation is captured in two-dimensional spectra, with species' phylogenetic relatedness moderately influencing coordination and trade-off between traits. Along the shoreline-inland gradient, aboveground traits support the LES in all habitats. Belowground traits are consistent with the RES in the back-habitat only, where the environmental constraints are weaker, and a coordination between leaf and root traits was also found, supporting the whole-plant spectrum (PES).center dot This study confirms the complexity when seeking any correlation between the LES and RES in ecosystems characterized by multiple environmental pressures, such as those investigated here. Changes in traits adopted to resist environmental constraints are similar among species, independent of their evolutionary relatedness, thus explaining the low phylogenetic contribution in support of our results

    Spin gating electrical current

    Full text link
    We use an aluminium single electron transistor with a magnetic gate to directly quantify the chemical potential anisotropy of GaMnAs materials. Uniaxial and cubic contributions to the chemical potential anisotropy are determined from field rotation experiments. In performing magnetic field sweeps we observe additional isotropic magnetic field dependence of the chemical potential which shows a non-monotonic behavior. The observed effects are explained by calculations based on the kâ‹…p\mathbf{k}\cdot\mathbf{p} kinetic exchange model of ferromagnetism in GaMnAs. Our device inverts the conventional approach for constructing spin transistors: instead of spin-transport controlled by ordinary gates we spin-gate ordinary charge transport.Comment: 5 pages, 4 figure

    Neurophysiological Vocal Source Modeling for Biomarkers of Disease

    Get PDF
    Speech is potentially a rich source of biomarkers for detecting and monitoring neuropsychological disorders. Current biomarkers typically comprise acoustic descriptors extracted from behavioral measures of source, filter, prosodic and linguistic cues. In contrast, in this paper, we extract vocal features based on a neurocomputational model of speech production, reflecting latent or internal motor control parameters that may be more sensitive to individual variation under neuropsychological disease. These features, which are constrained by neurophysiology, may be resilient to artifacts and provide an articulatory complement to acoustic features. Our features represent a mapping from a low-dimensional acoustics-based feature space to a high-dimensional space that captures the underlying neural process including articulatory commands and auditory and somatosensory feedback errors. In particular, we demonstrate a neurophysiological vocal source model that generates biomarkers of disease by modeling vocal source control. By using the fundamental frequency contour and a biophysical representation of the vocal source, we infer two neuromuscular time series whose coordination provides vocal features that are applied to depression and Parkinson’s disease as examples. These vocal source coordination features alone, on a single held vowel, outperform or are comparable to other features sets and reflect a significant compression of the feature space.United States. Air Force (Contract No. FA8721-05-C-0002)United States. Air Force (Contract No. FA8702-15- D-0001

    Reconfigurable Boolean Logic using Magnetic Single-Electron Transistors

    Full text link
    We propose a novel hybrid single-electron device for reprogrammable low-power logic operations, the magnetic single-electron transistor (MSET). The device consists of an aluminium single-electron transistors with a GaMnAs magnetic back-gate. Changing between different logic gate functions is realized by reorienting the magnetic moments of the magnetic layer which induce a voltage shift on the Coulomb blockade oscillations of the MSET. We show that we can arbitrarily reprogram the function of the device from an n-type SET for in-plane magnetization of the GaMnAs layer to p-type SET for out-of-plane magnetization orientation. Moreover, we demonstrate a set of reprogrammable Boolean gates and its logical complement at the single device level. Finally, we propose two sets of reconfigurable binary gates using combinations of two MSETs in a pull-down network
    • …
    corecore