327 research outputs found
Photonic qubits, qutrits and ququads accurately prepared and delivered on demand
Reliable encoding of information in quantum systems is crucial to all
approaches to quantum information processing or communication. This applies in
particular to photons used in linear optics quantum computing (LOQC), which is
scalable provided a deterministic single-photon emission and preparation is
available. Here, we show that narrowband photons deterministically emitted from
an atom-cavity system fulfill these requirements. Within their 500 ns coherence
time, we demonstrate a subdivision into d time bins of various amplitudes and
phases, which we use for encoding arbitrary qu-d-its. The latter is done
deterministically with a fidelity >95% for qubits, verified using a newly
developed time-resolved quantum-homodyne method.Comment: 5 pages, 4 figure
Two major ruminant acute phase proteins, haptoglobin and serum amyloid A, as serum biomarkers during active sheep scab infestation
Two ruminant acute phase proteins (APPs), haptoglobin (Hp) and serum amyloid A (SAA), were evaluated as serum biomarkers (BMs) for sheep scab–a highly contagious ectoparasitic disease caused by the mite Psoroptes ovis, which is a major welfare and production threat worldwide. The levels of both APPs increased in serum following experimental infestation of sheep with P. ovis, becoming statistically significantly elevated from pre-infestation levels at 4 weeks post-infestation. Following successful treatment of infested sheep with an endectocide, Hp and SAA serum levels declined rapidly, with half lives of less than 3 days. In contrast, serum IgG levels which specifically bound the P. ovis-derived diagnostic antigen Pso o 2 had a half-life of 56 days. Taking into account pre-infestation serum levels, rapidity of response to infestation and test sensitivity at the estimated optimum cut-off values, SAA was the more discriminatory marker. These studies illustrated the potential of SAA and Hp to indicate current sheep scab infestation status and to augment the existing Pso o 2 serological assay to give disease-specific indications of both infestation and successful treatment
Feeding-associated gene expression in sheep scab mites (Psoroptes ovis)
The mite Psoroptes ovis is the causative agent of sheep scab. Although not usually fatal, the disease can spread rapidly and is a serious animal welfare concern. Vaccine development against ectoparasites has primarily focussed on two sources of candidate vaccine antigens – “exposed” antigens that are secreted in saliva during feeding on a host and “concealed” antigens that are usually expressed in the parasite gut and may be involved in digestion. Here, we sought to identify genes encoding proteins important for mite feeding and digestion by a subtractive suppressive hybridisation approach comparing mRNA transcript abundance in “fed” and “starved” mites. The study identified a variety of genes which are up-regulated by feeding mites. These included group 1, 5, 7 and 13 allergens including the previously described cysteine protease Pso o 1. In addition, numerous novel genes were identified here including some encoding potential salivary gland proteins and others encoding proteins which may facilitate feeding such as a serum opacity factor. An olfactory receptor-like protein was identified in the starved mite population which may help the mite to identify a host
2010-2011 Master Class - Marc Reese and Ken Amis (Brass)
https://spiral.lynn.edu/conservatory_masterclasses/1079/thumbnail.jp
Photonic Quantum Logic with Narrowband Light from Single Atoms
Increasing control of single photons enables new applications of photonic
quantum-enhanced technology and further experimental exploration of fundamental
quantum phenomena. Here, we demonstrate quantum logic using narrow linewidth
photons that are produced under nearly perfect quantum control from a single
^87Rb atom strongly coupled to a high-finesse cavity. We use a controlled- NOT
gate integrated into a photonic chip to entangle these photons, and we observe
non-classical correlations between events separated by periods exceeding the
travel time across the chip by three orders of magnitude. This enables quantum
technology that will use the properties of both narrowband single photon
sources and integrated quantum photonics, such as networked quantum computing,
narrow linewidth quantum enhanced sensing and atomic memories.Comment: 5 pates, 3 figure
Highly Efficient Source for Indistinguishable Photons of Controlled Shape
We demonstrate a straightforward implementation of a push-button like
single-photon source which is based on a strongly coupled atom-cavity system.
The device operates intermittently for periods of up to 100 microseconds, with
single-photon repetition rates of 1.0 MHz and an efficiency of 60 %. Atoms are
loaded into the cavity using an atomic fountain, with the upper turning point
near the cavity's mode centre. This ensures long interaction times without any
disturbances induced by trapping potentials. The latter is the key to reaching
deterministic efficiencies as high as obtained in probabalistic
photon-heralding schemes. The price to pay is the random loading of atoms into
the cavity and the resulting intermittency. However, for all practical
purposes, this has a negligible impact
Restarting the conversation: challenges at the interface between ecology and society
8 páginas, 3 figuras, 2 tablas. -- Copyright by the Ecological Society of AmericaThe exchange of information between researchers, resource managers, decision makers, and the general public has long been recognized as a critical need in environmental science. We examine the challenges in using ecological knowledge to inform society and to change societal actions, and identify a set of options and strategies to enhance this exchange. Our objectives are to provide background information on societal knowledge and interest in science and environmental issues, to describe how different components of society obtain information and develop their interests and values, and to present a framework for evaluating and improving communication between science and society. Our analysis strongly suggests that the interface between science and society can only be improved with renewed dedication to public outreach and a wholesale reconsideration of the way that scientists communicate with society. Ecologists need to adopt new models of engagement with their audiences, frame their results in ways that are more meaningful to these audiences, and use new communication tools, capable of reaching large and diverse target groups.Este artĂculo está basado en unas presentaciones orales realizadas en 2009 Cary Conference. The Cary Conference fue financiada por la National Science Foundation (subvenciĂłn #DEB-0840224 y #0949558), el US Department of Agriculture (USDA) Forest Service (subvenciĂłn #09-DG-11132650-083), el US Environmental
Protection Agency (subvenciĂłn #EP09H000638), y el USDA Agriculture and Food Research Initiative Program.Peer reviewe
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