36,771 research outputs found
List of the Lepidoptera of Black Sturgeon Lake, Northwestern Ontario, and Dates of Adult Occurrence
From May to September each year from 1960 through 1968, a collection of Lepidoptera was made at Black Sturgeon Lake, northwestern Ontario, from speci mens captured in a light trap and from specimens netted during the day. A total of 564 species was recorded from 70 families. A list of the species with dates of capture is presented
Bounding quantum gate error rate based on reported average fidelity
Remarkable experimental advances in quantum computing are exemplified by
recent announcements of impressive average gate fidelities exceeding 99.9% for
single-qubit gates and 99% for two-qubit gates. Although these high numbers
engender optimism that fault-tolerant quantum computing is within reach, the
connection of average gate fidelity with fault-tolerance requirements is not
direct. Here we use reported average gate fidelity to determine an upper bound
on the quantum-gate error rate, which is the appropriate metric for assessing
progress towards fault-tolerant quantum computation, and we demonstrate that
this bound is asymptotically tight for general noise. Although this bound is
unlikely to be saturated by experimental noise, we demonstrate using explicit
examples that the bound indicates a realistic deviation between the true error
rate and the reported average fidelity. We introduce the Pauli distance as a
measure of this deviation, and we show that knowledge of the Pauli distance
enables tighter estimates of the error rate of quantum gates.Comment: New Journal of Physics Fast Track Communication. Gold open access
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Examining professionals' and parents' views of using transanal irrigation with children: Understanding their experiences to develop a shared health resource for education and practise
Irrigation as a bowel management approach has been reportedly used with children for more than 20 years. Parents managing their child's chronic bowel problem have previously been shown to have increased emotional stress. The aim of this study was to explore professionals' (n = 24) understanding and parents' (n = 18) experiences of using transanal irrigation with children at home as a mid to longer term bowel management approach. This study was underpinned by action research methodology and used mixed methods determined by an action research group of parents, professionals, researchers, a voluntary sector worker, commercial representative and independent observer. Data informed the study outcome which was the development and evaluation of a shared health resource to support professionals in their holistic approach when prescribing transanal irrigation and guide parents in the areas of education, management, problem solving, support and goal setting. The resource includes constructed case studies from parents of their experiences to inform choice and decision-making between parents and professionals. The shared health resource provides an approach to initiating and evaluating transanal irrigation and is available in a paper format from key Internet sites across hospital, community and voluntary services
Remote Preparation and Distribution of Bipartite Entangled States
We prove a powerful theorem for tripartite remote entanglement distribution
protocols that establishes an upper bound on the amount of entanglement of
formation that can be created between two single-qubit nodes of a quantum
network. Our theorem also provides an operational interpretation of concurrence
as a type of entanglement capacity.Comment: 5 pages, to appear in the Physical Review Letter
Long-distance quantum key distribution using concatenated entanglement swapping with practical resources
We present our approach for sharing photons and assessing resultant
four-photon visibility between two distant parties using concatenated
entanglement swapping. In addition we determine the corresponding key
generation rate and the quantum bit-error rate. Our model is based on practical
limitations of resources, including multipair parametric down-conversion
sources, inefficient detectors with dark counts and lossy channels. Through
this approach, we have found that a trade-off is needed between experimental
run-time, pair-production rate and detector efficiency. Concatenated
entanglement swapping enables huge distances for quantum key-distribution but
at the expense of low key generation rate
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