79 research outputs found

    Understanding Quantum Technologies 2022

    Full text link
    Understanding Quantum Technologies 2022 is a creative-commons ebook that provides a unique 360 degrees overview of quantum technologies from science and technology to geopolitical and societal issues. It covers quantum physics history, quantum physics 101, gate-based quantum computing, quantum computing engineering (including quantum error corrections and quantum computing energetics), quantum computing hardware (all qubit types, including quantum annealing and quantum simulation paradigms, history, science, research, implementation and vendors), quantum enabling technologies (cryogenics, control electronics, photonics, components fabs, raw materials), quantum computing algorithms, software development tools and use cases, unconventional computing (potential alternatives to quantum and classical computing), quantum telecommunications and cryptography, quantum sensing, quantum technologies around the world, quantum technologies societal impact and even quantum fake sciences. The main audience are computer science engineers, developers and IT specialists as well as quantum scientists and students who want to acquire a global view of how quantum technologies work, and particularly quantum computing. This version is an extensive update to the 2021 edition published in October 2021.Comment: 1132 pages, 920 figures, Letter forma

    Adaptive control of saccades

    Get PDF
    As we navigate through the world in our lifetime, our brains constantly adjust our movements to ensure their accuracy. How does the brain adaptively control our movements? In this dissertation, we looked at saccadic eye movements and performed behavioral and neural measurements to study different brain mechanisms for adaptive control of saccades. In ‎Chapter 2, we considered the effect of reward prediction error (RPE) as a strong modulator of dopamine on saccade vigor. We found that saccade vigor was affected in an orderly fashion by the magnitude and direction of the RPE event: the most vigorous saccades followed the largest positive-RPE, whereas the least vigorous saccades followed the largest negative-RPE. Thus, reward prediction error, and not reward per se, modulated the vigor of saccades. In ‎Chapter 3, we looked at corrective saccades during saccade adaptation and asked is there an implicit loss associated with the corrective movement that can modulate learning? We designed a novel paradigm that combined random dot motion discrimination with saccade adaptation to impose a cost on movement error. Our results demonstrated that when error cost was large, the brain learned more from error. Thus, during sensorimotor adaptation, the act of correcting for error carries an implicit cost for the brain which regulates the rates of learning. Next, we focused on the potential neural mechanisms for adaptive control of saccades and the role of the principal cells of the cerebellar cortex, Purkinje cells (P-cells), in control of saccades. We introduced marmoset monkeys as a new animal model to study motor control and motor learning. In ‎Chapter 4, we presented protocols to train marmoset monkeys to perform saccadic eye movement tasks and record from their cerebellum. In ‎Chapter 5, we introduced an open-source software package, named P-sort, to analyze the cerebellar neurophysiological data. Finally, in ‎Chapter 6, we analyzed the P-cell data (n=149 cells) by organizing them into populations that shared the same preference for error as measured via their complex spike response. We found that the population activity of simple spikes produced a burst-pause pattern that started before saccade onset and ended with saccade termination. Next, we looked at synchronous activity among pairs of simultaneously recorded P-cells (n=42 pairs). Our results demonstrated that the synchronization index reached its peak probability after deceleration onset but before saccade end. Thus, the cerebellar cortex relies on spike synchronization within a population of P-cells, not individual firing rates, to predict when to stop a movement

    The Rhetoric of Citizenship, Slavery, and Immigration: Fashioning a Language for Belonging in English Literature

    Get PDF
    With the rise of transnational migration, political factions ration the status of citizen against global diasporas, positioning citizenship as the primary space to assert opposition to hybrid forms of identity and multiculturalism. Simultaneously, however, contradictory ideals of inclusion compete using the same language, leading to confusions of citizenship rhetoric. This rhetoric—the vocabulary used to talk about citizenship, including in government legislation, in print and digital channels, and in everyday public life—obscures citizenship's deep normative divides, while exaggerating the nationalistic character of political membership. Located at the intersection of literary and citizenship studies, my dissertation constellates the literary text with issues of state governmentality and rhetorics of belonging in order to examine citizenship rhetoric from a literary perspective that is attentive to its affective and imaginary registers. Instead of citizenship as a form of rootedness, I foster a methodological approach that centres the role of movement—and in particular, the drive for authority over movement—in the imagining and practice of citizenship, in turn revealing the migratory and diasporic threads that underwrite modernity. While postcolonial and ethnicity studies have unravelled the complexity of national and ethnic belonging, my dissertation complements this existing scholarship by converging on citizenship rhetoric as a discursive formation shaped and altered by literature. I trace literature's role in configuring citizenship with sustained focus on Olaudah Equiano's The Interesting Narrative, Frances Burney's The Wanderer, Mary Shelley's travelogues and Frankenstein, Herman Melville's Benito Cereno, and Brian Friel's Translations. While historically rooted, this project is forward looking and considers how eighteenth and nineteenth century imaginings of the citizen still inform contemporary political practices

    EVOLUTION OF THE SUBCONTINENTAL LITHOSPHERE DURING MESOZOIC TETHYAN RIFTING: CONSTRAINTS FROM THE EXTERNAL LIGURIAN MANTLE SECTION (NORTHERN APENNINE, ITALY)

    Get PDF
    Our study is focussed on mantle bodies from the External Ligurian ophiolites, within the Monte Gavi and Monte Sant'Agostino areas. Here, two distinct pyroxenite-bearing mantle sections were recognized, mainly based on their plagioclase-facies evolution. The Monte Gavi mantle section is nearly undeformed and records reactive melt infiltration under plagioclase-facies conditions. This process involved both peridotites (clinopyroxene-poor lherzolites) and enclosed spinel pyroxenite layers, and occurred at 0.7–0.8 GPa. In the Monte Gavi peridotites and pyroxenites, the spinel-facies clinopyroxene was replaced by Ca-rich plagioclase and new orthopyroxene, typically associated with secondary clinopyroxene. The reactive melt migration caused increase of TiO2 contents in relict clinopyroxene and spinel, with the latter also recording a Cr2O3 increase. In the Monte Gavi peridotites and pyroxenites, geothermometers based on slowly diffusing elements (REE and Y) record high temperature conditions (1200-1250 °C) related to the melt infiltration event, followed by subsolidus cooling until ca. 900°C. The Monte Sant'Agostino mantle section is characterized by widespread ductile shearing with no evidence of melt infiltration. The deformation recorded by the Monte Sant'Agostino peridotites (clinopyroxene-rich lherzolites) occurred at 750–800 °C and 0.3–0.6 GPa, leading to protomylonitic to ultramylonitic textures with extreme grain size reduction (10–50 ÎŒm). Compared to the peridotites, the enclosed pyroxenite layers gave higher temperature-pressure estimates for the plagioclase-facies re-equilibration (870–930 °C and 0.8–0.9 GPa). We propose that the earlier plagioclase crystallization in the pyroxenites enhanced strain localization and formation of mylonite shear zones in the entire mantle section. We subdivide the subcontinental mantle section from the External Ligurian ophiolites into three distinct domains, developed in response to the rifting evolution that ultimately formed a Middle Jurassic ocean-continent transition: (1) a spinel tectonite domain, characterized by subsolidus static formation of plagioclase, i.e. the Suvero mantle section (Hidas et al., 2020), (2) a plagioclase mylonite domain experiencing melt-absent deformation and (3) a nearly undeformed domain that underwent reactive melt infiltration under plagioclase-facies conditions, exemplified by the the Monte Sant'Agostino and the Monte Gavi mantle sections, respectively. We relate mantle domains (1) and (2) to a rifting-driven uplift in the late Triassic accommodated by large-scale shear zones consisting of anhydrous plagioclase mylonites. Hidas K., Borghini G., Tommasi A., Zanetti A. & Rampone E. 2021. Interplay between melt infiltration and deformation in the deep lithospheric mantle (External Liguride ophiolite, North Italy). Lithos 380-381, 105855

    Impact of Etna’s volcanic emission on major ions and trace elements composition of the atmospheric deposition

    Get PDF
    Mt. Etna, on the eastern coast of Sicily (Italy), is one of the most active volcanoes on the planet and it is widely recognized as a big source of volcanic gases (e.g., CO2 and SO2), halogens, and a lot of trace elements, to the atmosphere in the Mediterranean region. Especially during eruptive periods, Etna’s emissions can be dispersed over long distances and cover wide areas. A group of trace elements has been recently brought to attention for their possible environmental and human health impacts, the Technology-critical elements. The current knowledge about their geochemical cycles is still scarce, nevertheless, recent studies (Brugnone et al., 2020) evidenced a contribution from the volcanic activity for some of them (Te, Tl, and REE). In 2021, in the framework of the research project “Pianeta Dinamico”, by INGV, a network of 10 bulk collectors was implemented to collect, monthly, atmospheric deposition samples. Four of these collectors are located on the flanks of Mt. Etna, other two are in the urban area of Catania and three are in the industrial area of Priolo, all most of the time downwind of the main craters. The last one, close to CesarĂČ (Nebrodi Regional Park), represents the regional background. The research aims to produce a database on major ions and trace element compositions of the bulk deposition and here we report the values of the main physical-chemical parameters and the deposition fluxes of major ions and trace elements from the first year of research. The pH ranged from 3.1 to 7.7, with a mean value of 5.6, in samples from the Etna area, while it ranged between 5.2 and 7.6, with a mean value of 6.4, in samples from the other study areas. The EC showed values ranging from 5 to 1032 ÎŒS cm-1, with a mean value of 65 ÎŒS cm-1. The most abundant ions were Cl- and SO42- for anions, Na+ and Ca+ for cations, whose mean deposition fluxes, considering all sampling sites, were 16.6, 6.8, 8.4, and 6.0 mg m-2 d, respectively. The highest deposition fluxes of volcanic refractory elements, such as Al, Fe, and Ti, were measured in the Etna’s sites, with mean values of 948, 464, and 34.3 ÎŒg m-2 d-1, respectively, higher than those detected in the other sampling sites, further away from the volcanic source (26.2, 12.4, 0.5 ÎŒg m-2 d-1, respectively). The same trend was also observed for volatile elements of prevailing volcanic origin, such as Tl (0.49 ÎŒg m-2 d-1), Te (0.07 ÎŒg m-2 d-1), As (0.95 ÎŒg m-2 d-1), Se (1.92 ÎŒg m-2 d-1), and Cd (0.39 ÎŒg m-2 d-1). Our preliminary results show that, close to a volcanic area, volcanic emissions must be considered among the major contributors of ions and trace elements to the atmosphere. Their deposition may significantly impact the pedosphere, hydrosphere, and biosphere and directly or indirectly human health

    Safe and Sound: Proceedings of the 27th Annual International Conference on Auditory Display

    Get PDF
    Complete proceedings of the 27th International Conference on Auditory Display (ICAD2022), June 24-27. Online virtual conference

    Digital work in the planetary market

    Get PDF
    Many of the world’s most valuable companies rely on planetary networks of digital work that underpin their products and services. This important book examines implications for both work and workers when jobs are commodified and traded beyond local labor markets. For instance, Amazon’s contractors in Costa Rica, India, and Romania are paid to structure, annotate, and organize conversations captured by ‘Alexa’ to train Amazon’s speech recognition systems. Findings show that despite its planetary connections, labor remains geographically “sticky” and embedded in distinct contexts. The research emphasizes the globe-spanning nature of contemporary networks without resorting to an understanding of “the global” as a place beyond space.Aujourd’hui, de nombreux emplois peuvent ĂȘtre exercĂ©s depuis n’importe oĂč. La technologie numĂ©rique et la connectivitĂ© Internet gĂ©nĂ©ralisĂ©e permettent Ă  presque n’importe qui, n’importe oĂč, de se connecter Ă  n’importe qui d’autre pour communiquer et interagir Ă  l’échelle planĂ©taire. Ce livre examine les consĂ©quences, tant pour le travail que pour les travailleurs, de la marchandisation et de l’échange des emplois au-delĂ  des marchĂ©s du travail locaux. Allant au-delĂ  du discours habituel sur la mondialisation « le monde est plat », les contributeurs examinent Ă  la fois la transformation du travail lui-mĂȘme et les systĂšmes, rĂ©seaux et processus plus larges qui permettent le travail numĂ©rique dans un marchĂ© planĂ©taire, en offrant des perspectives empiriques et thĂ©oriques. Les contributeurs - des universitaires et des experts de premier plan issus de diverses disciplines - abordent une variĂ©tĂ© de questions, notamment la modĂ©ration du contenu, les vĂ©hicules autonomes et les assistants vocaux. Ils se penchent d’abord sur la nouvelle expĂ©rience du travail et constatent que, malgrĂ© ses connexions planĂ©taires, le travail reste gĂ©ographiquement collĂ© et intĂ©grĂ© dans des contextes distincts. Ils examinent ensuite comment les rĂ©seaux planĂ©taires de travail peuvent ĂȘtre cartographiĂ©s et problĂ©matisĂ©s, ils discutent de la multiplicitĂ© productive et de l’interdisciplinaritĂ© de la rĂ©flexion sur le travail numĂ©rique et ses rĂ©seaux et, enfin, ils imaginent comment le travail planĂ©taire pourrait ĂȘtre rĂ©glementĂ©. Les directeurs Mark Graham est professeur de gĂ©ographie de l’Internet Ă  l’Oxford Internet Institute et chargĂ© de cours Ă  l’Alan Turing Institute. Il est l’éditeur du livre Digital Economies at Global Margins (MIT Press et CRDI, 2019). Fabian Ferrari est un candidat au doctorat Ă  l’Oxford Internet Institute
    • 

    corecore