186 research outputs found

    Best Model Identification: A Rested Bandit Formulation

    Get PDF
    We introduce and analyze a best arm identification problem in the rested bandit setting, wherein arms are themselves learning algorithms whose expected losses decrease with the number of times the arm has been played. The shape of the expected loss functions is similar across arms, and is assumed to be available up to unknown parameters that have to be learned on the fly. We define a novel notion of regret for this problem, where we compare to the policy that always plays the arm having the smallest expected loss at the end of the game. We analyze an arm elimination algorithm whose regret vanishes as the time horizon increases. The actual rate of convergence depends in a detailed way on the postulated functional form of the expected losses. We complement our analysis with lower bounds, indicating strengths and limitations of the proposed solution

    Tradition and Modernity in Italy, Portugal and Spain

    Get PDF
    DL 57/2016/CP1453/CT0041 UIDB/00749/2020 UIDP/00749/2020This volume emerges from an international seminar held at the Department of Historical Studies of the University of Turin on 2-4 October 2019, which brought together scholars from various academic and cultural institutions including, aside from the host department, the School of Social Sciences and Humanities of the NOVA University of Lisbon, the Institute of Social Sciences of the University of Lisbon, the Complutense University of Madrid, and the Centre for Studies on the Royal Savoy Residences in Reggia di Venaria Reale, Piedmont. It combines the outcomes of this meeting with other contributions of scientific relevance to the subject.publishersversionpublishe

    Images of Royalty in the Nineteenth and Twentieth Centuries. Tradition and Modernity in Italy, Portugal and Spain

    Get PDF
    This volume emerges from an international seminar held at the Department of Historical Studies of the University of Turin on 2-4 October 2019, which brought together scholars from various academic and cultural institutions including, aside from the host department, the School of Social Sciences and Humanities of the NOVA University of Lisbon, the Institute of Social Sciences of the University of Lisbon, the Complutense University of Madrid, and the Centre for Studies on the Royal Savoy Residences in Reggia di Venaria Reale, Piedmont. It combines the outcomes of this meeting with other contributions of scientific relevance to the subject. The editors’ aim has been to participate in the contemporary historical debate on monarchy, a topic of research that has accelerated markedly in recent years, as attested by the increase in academic colloquiums dedicated to it, such as the conference held in Cambridge in January 2019 under the title Monarchy and Modernity Since 1500, or the annual Kings and Queens Conferences that have been promoted by the Royal Studies Network since 2012.info:eu-repo/semantics/publishedVersio

    Differential Analysis of Gly211Val and Gly286Val Mutations Affecting Sarco(endo)plasmic Reticulum Ca2+-ATPase (SERCA1) in Congenital Pseudomyotonia Romagnola Cattle.

    Get PDF
    Congenital pseudomyotonia in cattle (PMT) is a rare skeletal muscle disorder, clinically characterized by stiffness and by delayed muscle relaxation after exercise. Muscle relaxation impairment is due to defective content of the Sarco(endo)plasmic Reticulum Ca2+ ATPase isoform 1 (SERCA1) protein, caused by missense mutations in the ATP2A1 gene. PMT represents the only mammalian model of human Brody myopathy. In the Romagnola breed, two missense variants occurring in the same allele were described, leading to Gly211Val and Gly286Val (G211V/G286V) substitutions. In this study, we analyzed the consequences of G211V and G286V mutations. Results support that the reduced amount of SERCA1 is a consequence of the G211V mutation, the G286V mutation almost being benign and the ubiquitin-proteasome system (UPS) being involved. After blocking the proteasome using a proteasome inhibitor, we found that the G211V mutant accumulates in cells at levels comparable to those of WT SERCA1. Our conclusion is that G211/286V mutations presumably originate in a folding-defective SERCA1 protein, recognized and diverted to degradation by UPS, although still catalytically functional, and that the main role is played by G211V mutation. Rescue of mutated SERCA1 to the sarcoplasmic reticulum membrane can re-establish resting cytosolic Ca2+ concentration and prevent the appearance of pathological signs, paving the way for a possible therapeutic approach against Brody disease

    Management models applied to the human-wolf conflict in agro-forestry-pastoral territories of two italian protected areas and one spanish game area

    Get PDF
    Our work shows that, despite the persistence of persecutory actions, conservation activity has proved successful for the return of numerous wild mammals to different habitats, including the wolf. The human-wolf conflict is still described in all countries where the wolf is present. This is evidenced by the high number of damages on livestock, and the corpses of wolves found both in protected areas and in those where hunting is permitted. The diagnosis of road accidents, together with poisoning and poaching, are major causes of mortality. Although hunting records the highest percentage of kills in Spain, the demographic stability reported by the censuses suggests that this activity does not have a consistent influence on the Iberian wolf population’s survival. In Italy, where wolf hunting is prohibited, wolf populations are to be increasing. In some Italian situations, wolf attacks on horses seem to cause unwanted damage to foals, but they represent a very precious source of information about the habits of carnivores. A simple management plan would be sufficient to help the coexistence between the productive parts and the ecosystem services ensured by the presence of the wolf. The presence of hybrids is a negative factor

    Learning Quantum Systems

    Full text link
    The future development of quantum technologies relies on creating and manipulating quantum systems of increasing complexity, with key applications in computation, simulation and sensing. This poses severe challenges in the efficient control, calibration and validation of quantum states and their dynamics. Although the full simulation of large-scale quantum systems may only be possible on a quantum computer, classical characterization and optimization methods still play an important role. Here, we review different approaches that use classical post-processing techniques, possibly combined with adaptive optimization, to learn quantum systems, their correlation properties, dynamics and interaction with the environment. We discuss theoretical proposals and successful implementations across different multiple-qubit architectures such as spin qubits, trapped ions, photonic and atomic systems, and superconducting circuits. This Review provides a brief background of key concepts recurring across many of these approaches with special emphasis on the Bayesian formalism and neural networks.Comment: Review. 20 pages, 4 figures and 2 boxes (reformatted

    Survival and divergence in a small group: The extraordinary genomic history of the endangered Apennine brown bear stragglers

    Get PDF
    About 100 km east of Rome, in the central Apennine Mountains, a critically endangered population of ∌50 brown bears live in complete isolation. Mating outside this population is prevented by several 100 km of bear-free territories. We exploited this natural experiment to better understand the gene and genomic consequences of surviving at extremely small population size. We found that brown bear populations in Europe lost connectivity since Neolithic times, when farming communities expanded and forest burning was used for land clearance. In central Italy, this resulted in a 40-fold population decline. The overall genomic impact of this decline included the complete loss of variation in the mitochondrial genome and along long stretches of the nuclear genome. Several private and deleterious amino acid changes were fixed by random drift; predicted effects include energy deficit, muscle weakness, anomalies in cranial and skeletal development, and reduced aggressiveness. Despite this extreme loss of diversity, Apennine bear genomes show nonrandom peaks of high variation, possibly maintained by balancing selection, at genomic regions significantly enriched for genes associated with immune and olfactory systems. Challenging the paradigm of increased extinction risk in small populations, we suggest that random fixation of deleterious alleles (i) can be an important driver of divergence in isolation, (ii) can be tolerated when balancing selection prevents random loss of variation at important genes, and (iii) is followed by or results directly in favorable behavioral changes
    • 

    corecore