128 research outputs found

    Scalable arrays of micro-Penning traps for quantum computing and simulation

    Full text link
    We propose the use of 2-dimensional Penning trap arrays as a scalable platform for quantum simulation and quantum computing with trapped atomic ions. This approach involves placing arrays of micro-structured electrodes defining static electric quadrupole sites in a magnetic field, with single ions trapped at each site and coupled to neighbors via the Coulomb interaction. We solve for the normal modes of ion motion in such arrays, and derive a generalized multi-ion invariance theorem for stable motion even in the presence of trap imperfections. We use these techniques to investigate the feasibility of quantum simulation and quantum computation in fixed ion lattices. In homogeneous arrays, we show that sufficiently dense arrays are achievable, with axial, magnetron and cyclotron motions exhibiting inter-ion dipolar coupling with rates significantly higher than expected decoherence. With the addition of laser fields these can realize tunable-range interacting spin Hamiltonians. We also show how local control of potentials allows isolation of small numbers of ions in a fixed array and can be used to implement high fidelity gates. The use of static trapping fields means that our approach is not limited by power requirements as system size increases, removing a major challenge for scaling which is present in standard radio-frequency traps. Thus the architecture and methods provided here appear to open a path for trapped-ion quantum computing to reach fault-tolerant scale devices.Comment: 21 pages, 10 figures Changes include adding section IX (Implementation Example) and substantially rewriting section X (Scaling

    Brigadas Rojas: oportunidad, estructura organizativa y evolución violenta

    Get PDF
    [ES] En el presente trabajo, se estudia el caso de las Brigadas Rojas desde una perspectiva estructural y agencial. La perspectiva estrucutral (correspondiente a el tránsito del fordismo al posfordismo y de la modernidad a la posmodernidad; así como el estudio de la capacidad del Estado italiano) permite comprender aquellos factores que sirvieron de oportunidad para el grupo armado italiano y la perspectiva agencial (correspondiente a la estructura organizativa y la evolución violenta) permite analizar el cambio acontecido en el movimiento

    De la biografía a la prosopografía: los parlamentarios de los distritos de Vasconia en la II República española (1931-1939)

    Get PDF
    Having carried out a micro-biographical analysis, using primary sources, of the 610 parliamentarians who represented the Basque districts between 1808 and 1939 in successive biographical dictionaries, we now undertake a prosopographical analysis of 44 parliamentarians who represented the districts of the Basque Country in the Spanish II Republic (1931-1939). Aspects covered include: geographical origin, age, life expectancy, educational and professional profile, cultural level and sociability, continuity in political activity between the Monarchy and the Republic. The work offers novel comparative conclusions.Realizado un análisis microbiográfico, con fuentes primarias, de los 610 parlamentarios que representaron a los distritos vascos entre 1808 y 1939 en sucesivos diccionarios biográficos, abordamos el análisis prosopográfico de los 44 parlamentarios que representaron a los distritos de Vasconia en la II República española (1931-1939): origen geográfico, edad, esperanza de vida, perfil educativo y profesional, nivel cultural y sociabilidad, continuidad en la actividad política entre la Monarquía y la República. El trabajo ofrece conclusiones comparativas novedosas

    Identification of loci associated with pathological outcomes in Holstein cattle infected with Mycobacterium avium subsp. paratuberculosis using whole-genome sequence data

    Get PDF
    [EN]Bovine paratuberculosis (PTB), caused by Mycobacterium avium subsp. paratuberculosis (MAP), is a chronic granulomatous enteritis that affects cattle worldwide. According to their severity and extension, PTB-associated histological lesions have been classified into the following groups; focal, multifocal, and diffuse. It is unknown whether these lesions represent sequential stages or divergent outcomes. In the current study, the associations between host genetic and pathology were explored by genotyping 813 Spanish Holstein cows with no visible lesions (N = 373) and with focal (N = 371), multifocal (N = 33), and diffuse (N = 33) lesions in gut tissues and regional lymph nodes. DNA from peripheral blood samples of these animals was genotyped with the bovine EuroG MD Bead Chip, and the corresponding genotypes were imputed to whole-genome sequencing (WGS) data using the 1000 Bull genomes reference population. A genome-wide association study (GWAS) was performed using the WGS data and the presence or absence of each type of histological lesion in a case-control approach. A total of 192 and 92 single nucleotide polymorphisms (SNPs) defining 13 and 9 distinct quantitative trait loci (QTLs) were highly-associated (P <= 5 x 10(-7)) with the multifocal (heritability = 0.075) and the diffuse (heritability = 0.189) lesions, respectively. No overlap was seen in the SNPs controlling these distinct pathological outcomes. The identified QTLs overlapped with some QTLs previously associated with PTB susceptibility, bovine tuberculosis susceptibility, clinical mastitis, somatic cell score, bovine respiratory disease susceptibility, tick resistance, IgG level, and length of productive life. Pathway analysis with candidate genes overlapping the identified QTLs revealed a significant enrichment of the keratinization pathway and cholesterol metabolism in the animals with multifocal and diffuse lesions, respectively. To test whether the enrichment of SNP variants in candidate genes involved in the cholesterol metabolism was associated with the diffuse lesions; the levels of total cholesterol were measured in plasma samples of cattle with focal, multifocal, or diffuse lesions or with no visible lesions. Our results showed reduced levels of plasma cholesterol in cattle with diffuse lesions. Taken together, our findings suggested that the variation in MAP-associated pathological outcomes might be, in part, genetically determined and indicative of distinct host responses.Financial support for this study was provided by a Grant from the Spanish Ministry of Science, Innovation, and Universities (RTI2018-094192-R-C21) and by European Regional Development Funds (FEDER) to MAH. MC and GBB have been awarded fellowships from the National Institute for Agricultural Research (INIA) and the Spanish Ministry of Science, Innovation and Universities programs, respectively. This work has been possible thanks to the support of the computing infrastructure of the i2BASQUE Research and Academic Network. We gratefully acknowledge the Bull Genomes Consortium for providing accessibility to the WGS data that was used in this study. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

    Qualitative Methodology in the Study of Traditional Games

    Get PDF
    Este trabajo está bajo la licencia Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License. Las imágenes u otro material de terceros en este artículo se incluyen en la licencia Creative Commons del artículo, a menos que se indique lo contrario en la línea de crédito. Si el material no está incluido en la licencia Creative Commons, los usuarios deberán obtener el permiso del titular de la licencia para reproducir el material.Este texto presenta una manera de aplicar la metodología cualitativa para estudiar la vivencia emocional que originan diferentes categorías de juego motor. Esta propuesta se contextualiza en las bases teóricas de la educación de conductas motrices y en el uso de métodos mixtos. Se explican las tres fases de análisis de contenido aplicado a comentarios de distintos grupos de participantes de España, Portugal, Suiza y Brasil (universitarios, de educación primaria y secundaria), obtenidos mediante el cuestionario validado Games and Emotion Scale (GES) y entrevistas rememoradas. Esta línea de investigación ha permitido elaborar mapas conceptuales interpretativos de la vivencia emocional de los distintos tipos de juegos y a su vez presentar propuestas educativas para los profesionales de una educación física moderna.This text presents one way to apply the qualitative methodology to study the emotional experience sparked by different categories of motor games. This proposal is contextualized in the theoretical underpinnings of the education of motor behaviors and in the use of mixed methodologies. The three phases of content analysis are explained applied to comments from different groups of participants in Spain, Portugal, Switzerland and Brazil (university students and primary and secondary school students) gotten from the validated Games and Emotion Scale (GES) questionnaire and reflective interviews. This avenue of research has enabled conceptual maps interpreting the emotional experience of the different kinds of games to be developed and educational proposals for professionals in modern physical education to be presented

    MaRCoS, an open-source electronic control system for low-field MRI

    Full text link
    Every magnetic resonance imaging (MRI) device requires an electronic control system that handles pulse sequences and signal detection and processing. Here we provide details on the architecture and performance of MaRCoS, a MAgnetic Resonance COntrol System developed by an open international community of low-field MRI researchers. MaRCoS is inexpensive and can handle cycle-accurate sequences without hard length limitations, rapid bursts of events, and arbitrary waveforms. It can also be easily adapted to meet further specifications required by the various academic and private institutions participating in its development. We describe the MaRCoS hardware, firmware and software that enable all of the above, including a Python-based graphical user interface for pulse sequence implementation, data processing and image reconstruction.Comment: 10 pages, 4 figure

    The first comprehensive micro use-wear analysis of an early Acheulean assemblage (Thiongo Korongo, Olduvai Gorge, Tanzania)

    Get PDF
    Probably, one of the biggest questions about the Acheulean is focused on the functional aspects of its lithic industry and, more specifically, its link to subsistence activities developed by hominins during the Early Stone Age. Historically, tecno-functional research on ESA techno-complex has focused on the role played by flakes and LCT in the processing of animal carcasses, but less attention has been payed to other possible activities related with subsistence and tool making. Previous traceological studies on African Lower Paleolithic lithic industries have shown the complexity of activities made with the earliest lithic tools, including not only the processing of animal carcasses, but also activities dedicated to processing wood, non-woody plants and underground storage organs (USOs). In this paper we present the use-wear results obtained from the analysis of the Early Acheulean lithic tools with potentially functional edges which are part of the lithic assemblage from the Thiongo Korongo archaeological site (TK) (Olduvai Gorge, Tanzania). The three main levels of the archaeological site, TKSF, TKLSC and TKLF, have been used as samples. From 466 lithic artefacts analyzed, 16 pieces present sufficient preservation of use related traces that are able to clearly identify the activities developed when compared with experimental reference collections. As a result, we have identified activities mainly related with the cutting and scraping of wood and non-woody plants, including USOs. In addition, some pieces have also presented traces indicating the processing of animal carcasses. These data provides important information about different activities developed in TK by early hominids, allowing us to make broader inferences about the different subsistence activities carried out during the Acheulean in Eastern Africa.Depto. de Prehistoria, Historia Antigua y ArqueologíaFac. de Geografía e HistoriaTRUEMinisterio de Ciencia e Innovación (MICINN)pu
    corecore