1,477 research outputs found

    A simple operational interpretation of the fidelity

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    This note presents a corollary to Uhlmann's theorem which provides a simple operational interpretation for the fidelity of mixed states.Comment: 1 pag

    Meta-Analysis of Cyathostomin Species-Specific Prevalence and Relative Abundance in Domestic Horses from 1975-2020: Emphasis on Geographical Region and Specimen Collection Method

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    BACKGROUND: Cyathostomins infect virtually all horses, and concomitant infections with 10 or more species per horse is standard. Species-specific knowledge is limited, despite potential species bias in development of disease and anthelmintic resistance. This is the first meta-analysis to examine effects of geographical region and cyathostomin collection method on reported composition of cyathostomin communities. METHODS: Thirty-seven articles published in English in 1975 or later, in which adults of individual species were systematically enumerated, were included. Seven regions; North America, South America, eastern Europe, western Europe, northern Europe, southern Africa, and Oceania, and three cyathostomin collection methods; (i) standard necropsy recovery from the large intestine, (ii) critical test collection from post-treatment feces and necropsy, and (iii) diagnostic deworming recovery solely from post-treatment feces, were considered. Generalized mixed linear models analyzed the effects of region and collection method on species-specific prevalence and relative abundance. Species richness was analyzed by mixed linear models. RESULTS: Definitively, the most prevalent and relatively abundant species were Cylicocyclus nassatus (prevalence = 93%, relative abundance = 20%), Cylicostephanus (Cys.) longibursatus (93%, 20%), and Cyathostomum catinatum (90%, 16%). A bias toward horses with high infection intensities and cyathostomin collection from feces resulted in North American critical tests and eastern European diagnostic deworming overestimating the species-specific prevalence and underestimating the relative abundance of rare/uncommon species compared to respective intra-regional standard necropsies. North American critical tests underestimated species richness due partially to identification key errors. Inter-regional standard necropsy comparisons yielded some species-specific regional differences, including a significantly higher Cys. longibursatus prevalence and relative abundance in North America (92%, 33%) than in eastern Europe (51%, 7%) (P \u3e 0.0001). Localization of critical tests to North America and diagnostic deworming to Eastern Europe precluded expansive ‘region by collection method’ interaction analyses. CONCLUSION: We provide substantial data to inform study design, e.g. effect and study size, for cyathostomin research and highlight necessity for method standardization and raw data accessibility for optimal post-factum comparisons

    A practical scheme for quantum computation with any two-qubit entangling gate

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    Which gates are universal for quantum computation? Although it is well known that certain gates on two-level quantum systems (qubits), such as the controlled-not (CNOT), are universal when assisted by arbitrary one-qubit gates, it has only recently become clear precisely what class of two-qubit gates is universal in this sense. Here we present an elementary proof that any entangling two-qubit gate is universal for quantum computation, when assisted by one-qubit gates. A proof of this important result for systems of arbitrary finite dimension has been provided by J. L. and R. Brylinski [arXiv:quant-ph/0108062, 2001]; however, their proof relies upon a long argument using advanced mathematics. In contrast, our proof provides a simple constructive procedure which is close to optimal and experimentally practical [C. M. Dawson and A. Gilchrist, online implementation of the procedure described herein (2002), http://www.physics.uq.edu.au/gqc/].Comment: 3 pages, online implementation of procedure described can be found at http://www.physics.uq.edu.au/gqc

    The role of microarthropods in emerging models of soil organic matter

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    A new understanding of soil organic matter (SOM) formation and stabilization has emerged over the past decade, highlighting the importance of microbial activity, mineral association of organic matter and aggregate occlusion of organic matter to SOM persistence. To date, the contribution of microarthropods to litter decomposition and SOM formation processes has not received due consideration and theoretical and empirical models should be modified to include how these organisms impact SOM protection. Here, we highlight the biological, chemical and physical mechanisms by which microarthropods influence SOM formation both directly and indirectly. Although more data is needed to quantify the impacts of different microarthropods on SOM dynamics, we highlight areas where inclusion of microarthropods in emerging models of SOM formation could reduce model uncertainties

    Incidence of WISE -selected obscured AGNs in major mergers and interactions from the SDSS

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    We use the Wide-field Infrared Survey Explorer (WISE) and the Sloan Digital Sky Survey (SDSS) to confirm a connection between dust-obscured active galactic nuclei (AGNs) and galaxy merging. Using a new, volume-limited (z ≤ 0.08) catalogue of visually selected major mergers and galaxy–galaxy interactions from the SDSS, with stellar masses above 2 × 1010 M⊙, we find that major mergers (interactions) are 5–17 (3–5) times more likely to have red [3.4] − [4.6] colours associated with dust-obscured or ‘dusty’ AGNs, compared to non-merging galaxies with similar masses. Using published fibre spectral diagnostics, we map the [3.4] − [4.6] versus [4.6] − [12] colours of different emission-line galaxies and find that one-quarter of Seyferts have colours indicative of a dusty AGN. We find that AGNs are five times more likely to be obscured when hosted by a merging galaxy, half of AGNs hosted by a merger are dusty, and we find no enhanced frequency of optical AGNs in merging over non-merging galaxies. We conclude that undetected AGNs missed at shorter wavelengths are at the heart of the ongoing AGN-merger connection debate. The vast majority of mergers hosting dusty AGNs are star forming and located at the centres of Mhalo < 1013 M⊙ groups. Assuming plausibly short-duration dusty-AGN phases, we speculate that a large fraction of gas-rich mergers experience a brief obscured AGN phase, in agreement with the strong connection between central star formation and black hole growth seen in merger simulations

    Universal quantum computation and simulation using any entangling Hamiltonian and local unitaries

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    What interactions are sufficient to simulate arbitrary quantum dynamics in a composite quantum system? We provide an efficient algorithm to simulate any desired two-body Hamiltonian evolution using any fixed two-body entangling n-qubit Hamiltonian and local unitaries. It follows that universal quantum computation can be performed using any entangling interaction and local unitary operations.Comment: Added references to NMR refocusing and to earlier work by Leung et al and Jones and Knil

    Population structure and connectivity of tiger sharks (Galeocerdo cuvier) across the Indo-Pacific Ocean basin

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    Population genetic structure using nine polymorphic nuclear microsatellite loci was assessed for the tiger shark () at seven locations across the Indo-Pacific, and one location in the southern Atlantic. Genetic analyses revealed considerable genetic structuring ( > 0.14,

    NADPH oxidase, NOX1, mediates vascular injury in ischemic retinopathy

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    &lt;b&gt;Aims:&lt;/b&gt; Ischemic retinal diseases such as retinopathy of prematurity are major causes of blindness due to damage to the retinal microvasculature. Despite this clinical situation, retinopathy of prematurity is mechanistically poorly understood. Therefore, effective preventative therapies are not available. However, hypoxic-induced increases in reactive oxygen species (ROS) have been suggested to be involved with NADPH oxidases (NOX), the only known dedicated enzymatic source of ROS. Our major aim was to determine the contribution of NOX isoforms (1, 2, and 4) to a rodent model of retinopathy of prematurity. &lt;b&gt;Results:&lt;/b&gt; Using a genetic approach, we determined that only mice with a deletion of NOX1, but not NOX2 or NOX4, were protected from retinal neovascularization and vaso-obliteration, adhesion of leukocytes, microglial accumulation, and the increased generation of proangiogenic and proinflammatory factors and ROS. We complemented these studies by showing that the specific NOX inhibitor, GKT137831, reduced vasculopathy and ROS levels in retina. The source of NOX isoforms was evaluated in retinal vascular cells and neuro-glial elements. Microglia, the immune cells of the retina, expressed NOX1, 2, and 4 and responded to hypoxia with increased ROS formation, which was reduced by GKT137831. &lt;b&gt;Innovation:&lt;/b&gt; Our studies are the first to identify the NOX1 isoform as having an important role in the pathogenesis of retinopathy of prematurity. &lt;b&gt;Conclusions:&lt;/b&gt; Our findings suggest that strategies targeting NOX1 have the potential to be effective treatments for a range of ischemic retinopathie
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