4,832 research outputs found

    Guaranteed emergence of genuine entanglement in 3-qubit evolving systems

    Full text link
    Multipartite entanglement has been shown to be of particular relevance for a better understanding and exploitation of the dynamics and flow of entanglement in multiparty systems. This calls for analysis aimed at identifying the appropriate processes that guarantee the emergence of multipartite entanglement in a wide range of scenarios. Here we carry on such analysis considering a system of two initially entangled qubits, one of which is let to interact with a third qubit according to an arbitrary unitary evolution. We establish necessary and sufficient conditions on the corresponding Kraus operators, to discern whether the evolved state pertains to either one of the classes of 3-qubit pure states that exhibit some kind of entanglement, namely biseparable, W-, and GHZ- genuine entangled classes. Our results provide a classification of the Kraus operators according to their capacity of producing 3-qubit entanglement, and pave the way for extending the analysis to larger systems and determining the particular interactions that must be implemented in order to create, enhance and distribute entanglement in a specific manner.Comment: Two new subsections included. Accepted for publication in The European Physical Journal

    The Effects of Two Computer-Based Reading Software Programs on Student Reading Performance

    Get PDF
    Reading below grade level at the elementary level continues to be an ongoing nationwide trend in many schools. With an increasing amount of struggling readers and the rising use of educational technology, it is important for school systems to understand the effectiveness of various types of available technology applications to support student reading performance among struggling readers. With this in mind, school systems must know how to determine which technology applications are more effective for increasing student performance with reading. This study focused on two computer-based reading software programs that claim to aid in improving student reading performance, ABCmouse and Starfall. Participants included 20 second grade students who were randomly assigned to two comparison groups. Data from this technology-based intervention was collected and analyzed to determine which reading software programs had the greatest impact on student performance with reading

    Stolen Wages in the Nation's Capital: Fixing DC's Broken Wage Theft Claims Process

    Get PDF
    Today in the District of Columbia ("the District" or "DC"), low wage workers are being shortchanged. Policies currently in place make it very difficult, to nearly impossible, for victims of wage theft to hold employers accountable for failing to pay wages owed. The Wage Theft Prevention Act of 2014, co-introduced on February 4, 2014 by Councilmembers Vincent Orange, Jim Graham, and Mary Cheh, would provide needed accountability and stronger protections to ensure that those working an honest day receive honest pay for their labor. This document provides an introduction to the current barriers affecting workers in the District, and presents an overview of the ways in which the Wage Theft Prevention Act of 2014 would ameliorate these problems; thereby making the District a better place for workers and responsible businesses

    Mucuna tapantiana (Fabaceae: Faboideae: Phaseoleae), a new species from Costa Rica

    Get PDF
    A new species of Mucuna (Fabaceae: Faboideae: Phaseoleae), endemic to Costa Rica, is described and illustrated. Mucuna tapantiana is distinguished by its small, essentially glabrous leaflets, conspicuous filiform peduncle and pedicels, inflorescences with few green or yellowish-green flowers; fruits with softly villous, yellowish or brownish pubescence on the outer surface (when fresh), but without urticating trichomes, turning dark brown or blackish when dry, 1 - 2-seeded; seeds oblong and laterally compressed691COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESMissouri Botanical Garden; Universidad Estadual at Campina

    Spatial and taxonomic biases in bat records: drivers and conservation implications in a megadiverse country

    Get PDF
    Biases in data availability have serious consequences on scientific inferences that can be derived. The potential consequences of these biases could be more detrimental in the less‐studied megadiverse regions, often characterized by high biodiversity and serious risks of human threats, as conservation and management actions could be misdirected. Here, focusing on 134 bat species in Mexico, we analyze spatial and taxonomic biases and their drivers in occurrence data; and identify priority areas for further data collection which are currently under‐sampled or at future environmental risk. We collated a comprehensive database of 26,192 presence‐only bat records in Mexico to characterize taxonomic and spatial biases and relate them to species' characteristics (range size and foraging behavior). Next, we examined variables related to accessibility, species richness and security to explain the spatial patterns in occurrence records. Finally, we compared the spatial distributions of existing data and future threats to these species to highlight those regions that are likely to experience an increased level of threats but are currently under‐surveyed. We found taxonomic biases, where species with wider geographical ranges and narrow‐space foragers (species easily captured with traditional methods), had more occurrence data. There was a significant oversampling toward tropical regions, and the presence and number of records was positively associated with areas of high topographic heterogeneity, road density, urban, and protected areas, and negatively associated with areas which were predicted to have future increases in temperature and precipitation. Sampling efforts for Mexican bats appear to have focused disproportionately on easily captured species, tropical regions, areas of high species richness and security; leading to under‐sampling in areas of high future threats. These biases could substantially influence the assessment of current status of, and future anthropogenic impacts on, this diverse species group in a tropical megadiverse country

    NAFTA and the Regulation of Financial and Other Services

    Get PDF
    This PDF contains a central article and response articles, these are then followed by a short discussion piece

    The Area Quantum and Snyder Space

    Get PDF
    We show that in the Snyder space the area of the disc and of the sphere can be quantized. It is also shown that the area spectrum of the sphere can be related to the Bekenstein conjecture for the area spectrum of a black hole horizon.Comment: 7 pages, in Press, Physics Letters

    Analysis and forecast of performance characteristics of combine harvesters

    Get PDF
    ArticleThis article presents results of an experimental research of qualitative indicators of the modern combine harvesters (Case IH Axil Flow 8230, MasseyFergusonMFT7, JohnDeereS680i, ClaasLexion760, NewHolland CR9.80) used for winter wheat harvesting. Based on the results obtained, determination was made regarding the productivity of combine harvesters on the field, fuel consumption, and field conditions influence the grain loss and grain damage caused by a harvester. When conducting the experimental research of a combine's performance on the field a study of the effectiveness of the combine JohnDeereS680i was made on different modes. A program 'Machine Unit', designed by the authors, was used for the determination of productivity, fuel consumption and quality indicator for harvesting
    corecore