199 research outputs found
Efficient Parity Encoded Optical Quantum Computing
We present a linear optics quantum computation scheme with a greatly reduced
cost in resources compared to KLM. The scheme makes use of elements from
cluster state computation and achieves comparable resource usage to those
schemes while retaining the circuit based approach of KLM
Loss-tolerant operations in parity-code linear optics quantum computing
A heavy focus for optical quantum computing is the introduction of
error-correction, and the minimisation of resource requirements. We detail a
complete encoding and manipulation scheme designed for linear optics quantum
computing, incorporating scalable operations and loss-tolerant architecture.Comment: 8 pages, 6 figure
Loss Tolerant Optical Qubits
We present a linear optics quantum computation scheme that employs a new
encoding approach that incrementally adds qubits and is tolerant to photon loss
errors. The scheme employs a circuit model but uses techniques from cluster
state computation and achieves comparable resource usage. To illustrate our
techniques we describe a quantum memory which is fault tolerant to photon loss
Fault Tolerance in Parity-State Linear Optical Quantum Computing
We use a combination of analytical and numerical techniques to calculate the
noise threshold and resource requirements for a linear optical quantum
computing scheme based on parity-state encoding. Parity-state encoding is used
at the lowest level of code concatenation in order to efficiently correct
errors arising from the inherent nondeterminism of two-qubit linear-optical
gates. When combined with teleported error-correction (using either a Steane or
Golay code) at higher levels of concatenation, the parity-state scheme is found
to achieve a saving of approximately three orders of magnitude in resources
when compared to a previous scheme, at a cost of a somewhat reduced noise
threshold.Comment: LaTeX, 10 pages, introduction updated for journal submissio
Multistate Assessment of Public Health Surveillance Relevant to American Indians and Alaska Natives, 2007
Improving the health of American Indian and Alaska Native (AI/AN) populations involves multiple agencies, levels of government, and jurisdictions. We assessed collaboration between state health departments and AI/AN Tribes and agencies through an online survey of State Epidemiologists. Frequencies and percentages of responses were examined by univariate and bivariate analyses. Among 39 states with federally recognized or state-recognized Tribes or federally funded urban Indian health centers, 25 (64%) participated. Nineteen had discussed public health surveillance with an AI/ AN government or nongovernment entity in the past 2 years (10 (53%) of these had ongoing, regular discussions about public health surveillance; nine (47%) had these discussions as needed). Nine (36%) responding states have a point person for working with AI/AN communities and/or agencies on public health surveillance. Four (16%) states have an active memorandum of understanding or other formal agreement with an AI/AN government or nongovernment entity regarding surveillance. To prepare for public health emergencies, six (24%) states involve the Indian Health Service, and eight (47%) involve another AI/AN entity. Functional relationships between state health departments and AI/AN agencies have not been consistently established. Strengthening these relationships will facilitate surveillance and response capacity to address continuing and emerging public health problems
Quantum Optical Systems for the Implementation of Quantum Information Processing
We review the field of Quantum Optical Information from elementary
considerations through to quantum computation schemes. We illustrate our
discussion with descriptions of experimental demonstrations of key
communication and processing tasks from the last decade and also look forward
to the key results likely in the next decade. We examine both discrete (single
photon) type processing as well as those which employ continuous variable
manipulations. The mathematical formalism is kept to the minimum needed to
understand the key theoretical and experimental results
Local versus global strategies in multi-parameter estimation
We consider the problem of estimating multiple phases using a multi-mode interferometer. In this setting we show that while global strategies that estimate all the phases simultaneously can lead to high precision gains, the same enhancements can be obtained with local strategies where each phase is estimated individually. A key resource for the enhancement is shown to be a large particle-number variance in the probe state, and for states where the total particle number is not fixed, this can be obtained for mode-separable states and the phases can be read out with local measurements. This has important practical implications because local strategies are generally preferred to global ones for their robustness to local estimation failure, flexibility in the distribution of resources, and comparatively easier state preparation. We obtain our results by analyzing two different schemes: the first uses a set of interferometers, which can be used as a model for a network of quantum sensors, and the second looks at measuring a number of phases relative to a reference, which is concerned primarily with quantum imaging
30 days wild: development and evaluation of a large-scale nature engagement campaign to improve well-being
There is a need to increase people’s engagement with and connection to nature, both for human well-being and the conservation of nature itself. In order to suggest ways for people to engage with nature and create a wider social context to normalise nature engagement, The Wildlife Trusts developed a mass engagement campaign, 30 Days Wild. The campaign asked people to engage with nature every day for a month. 12,400 people signed up for 30 Days Wild via an online sign-up with an estimated 18,500 taking part overall, resulting in an estimated 300,000 engagements with nature by participants. Samples of those taking part were found to have sustained increases in happiness, health, connection to nature and pro-nature behaviours. With the improvement in health being predicted by the improvement in happiness, this relationship was mediated by the change in connection to nature
Single nucleotide polymorphism discovery in rainbow trout by deep sequencing of a reduced representation library
<p>Abstract</p> <p>Background</p> <p>To enhance capabilities for genomic analyses in rainbow trout, such as genomic selection, a large suite of polymorphic markers that are amenable to high-throughput genotyping protocols must be identified. Expressed Sequence Tags (ESTs) have been used for single nucleotide polymorphism (SNP) discovery in salmonids. In those strategies, the salmonid semi-tetraploid genomes often led to assemblies of paralogous sequences and therefore resulted in a high rate of false positive SNP identification. Sequencing genomic DNA using primers identified from ESTs proved to be an effective but time consuming methodology of SNP identification in rainbow trout, therefore not suitable for high throughput SNP discovery. In this study, we employed a high-throughput strategy that used pyrosequencing technology to generate data from a reduced representation library constructed with genomic DNA pooled from 96 unrelated rainbow trout that represent the National Center for Cool and Cold Water Aquaculture (NCCCWA) broodstock population.</p> <p>Results</p> <p>The reduced representation library consisted of 440 bp fragments resulting from complete digestion with the restriction enzyme <it>Hae</it>III; sequencing produced 2,000,000 reads providing an average 6 fold coverage of the estimated 150,000 unique genomic restriction fragments (300,000 fragment ends). Three independent data analyses identified 22,022 to 47,128 putative SNPs on 13,140 to 24,627 independent contigs. A set of 384 putative SNPs, randomly selected from the sets produced by the three analyses were genotyped on individual fish to determine the validation rate of putative SNPs among analyses, distinguish apparent SNPs that actually represent paralogous loci in the tetraploid genome, examine Mendelian segregation, and place the validated SNPs on the rainbow trout linkage map. Approximately 48% (183) of the putative SNPs were validated; 167 markers were successfully incorporated into the rainbow trout linkage map. In addition, 2% of the sequences from the validated markers were associated with rainbow trout transcripts.</p> <p>Conclusion</p> <p>The use of reduced representation libraries and pyrosequencing technology proved to be an effective strategy for the discovery of a high number of putative SNPs in rainbow trout; however, modifications to the technique to decrease the false discovery rate resulting from the evolutionary recent genome duplication would be desirable.</p
Cognitive Information Processing
Contains research objectives and summary of research on fourteen research projects and reports on four research projects.Joint Services Electronics Program (Contract DAAB07-75-C-1346)National Science Foundation (Grant EPP74-12653)National Science Foundation (Grant ENG74-24344)National Institutes of Health (Grant 2 PO1 GM19428-04)Swiss National Funds for Scientific ResearchM.I.T. Health Sciences Fund (Grant 76-11)National Institutes of Health (Grant F03 GM58698)National Institutes of Health (Biomedical Sciences Support Grant)Associated Press (Grant
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