8,053 research outputs found

    Current US algae biorefineries, projects and perspectives

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    Large challenges remain to take advantage of algae (cyanobacteria, microalgae, and macroalgae) as a bioenergy, biofuels, and bioproducts crop. Traditional applications in the nutraceutical and food industry, have shown more promise. New efforts in combining a biorefinery approach with wastewater treatment, anaerobic digestion, and biomass utilization are becoming more popular and successful towards providing a middle ground for implementation of algae cultivation systems. An overview will be provided of the growth in fundamental and applied algae research in recent years, which will include a review of the scientific literature and key programs in bioenergy in the US leading to a resurgence and interest in algae. With this presentation, a discussion will ensue on the challenges being tackled to make the algae biorefinery a viable industry, including progress and opportunities available to develop algae as a key crop for the bioenergy and the bioproducts industries.Universidad de MĂĄlaga.Campus de Excelencia Internacional Andalucia Tec

    Selective cloning of Gaussian states by linear optics

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    We investigate the performances of a selective cloning machine based on linear optical elements and Gaussian measurements, which allows to clone at will one of the two incoming input states. This machine is a complete generalization of a 1 to 2 cloning scheme demonstrated by U. L. Andersen et al. [Phys. Rev. Lett. vol. 94, 240503 (2005)]. The input-output fidelity is studied for generic Gaussian input state and the effect of non-unit quantum efficiency is also taken into account. We show that if the states to be cloned are squeezed states with known squeezing parameter, then the fidelity can be enhanced using a third suitable squeezed state during the final stage of the cloning process. A binary communication protocol based on the selective cloning machne is also discussed.Comment: 6 pages, 6 figure

    Photon subtracted states and enhancement of nonlocality in the presence of noise

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    We address nonlocality of continuous variable systems in the presence of dissipation and noise. Three nonlocality tests have been considered, based on the measurement of displaced-parity, field-quadrature and pseudospin-operator, respectively. Nonlocality of twin beam has been investigated, as well as that of its non-Gaussian counterparts obtained by inconclusive subtraction of photons. Our results indicate that: i) nonlocality of twin beam is degraded but not destroyed by noise; ii) photon subtraction enhances nonlocality in the presence of noise, especially in the low-energy regime.Comment: 12 pages, 7 figure

    Degaussification of twin-beam and nonlocality in the phase space

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    We show that inconclusive photon subtraction (IPS) on twin-beam produces non-Gaussian states that violate Bell's inequality in the phase-space. The violation is larger than for the twin-beam itself irrespective of the IPS quantum efficiency. The explicit expression of IPS map is given both for the density matrix and the Wigner function representations.Comment: 7 pages, 6 figure

    The big five: Discovering linguistic characteristics that typify distinct personality traits across Yahoo! answers members

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    IndexaciĂłn: Scopus.This work was partially supported by the project FONDECYT “Bridging the Gap between Askers and Answers in Community Question Answering Services” (11130094) funded by the Chilean Government.In psychology, it is widely believed that there are five big factors that determine the different personality traits: Extraversion, Agreeableness, Conscientiousness and Neuroticism as well as Openness. In the last years, researchers have started to examine how these factors are manifested across several social networks like Facebook and Twitter. However, to the best of our knowledge, other kinds of social networks such as social/informational question-answering communities (e.g., Yahoo! Answers) have been left unexplored. Therefore, this work explores several predictive models to automatically recognize these factors across Yahoo! Answers members. As a means of devising powerful generalizations, these models were combined with assorted linguistic features. Since we do not have access to ask community members to volunteer for taking the personality test, we built a study corpus by conducting a discourse analysis based on deconstructing the test into 112 adjectives. Our results reveal that it is plausible to lessen the dependency upon answered tests and that effective models across distinct factors are sharply different. Also, sentiment analysis and dependency parsing proven to be fundamental to deal with extraversion, agreeableness and conscientiousness. Furthermore, medium and low levels of neuroticism were found to be related to initial stages of depression and anxiety disorders. © 2018 Lithuanian Institute of Philosophy and Sociology. All rights reserved.https://www.cys.cic.ipn.mx/ojs/index.php/CyS/article/view/275

    De-Gaussification by inconclusive photon subtraction

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    We address conditional de-Gaussification of continuous variable states by inconclusive photon subtraction (IPS) and review in details its application to bipartite twin-beam state of radiation. The IPS map in the Fock basis has been derived, as well as its counterpart in the phase-space. Teleportation assisted by IPS states is analyzed and the corresponding fidelity evaluated as a function of the involved parameters. Nonlocality of IPS states is investigated by means of different tests including displaced parity, homodyne detection, pseudospin, and displaced on/off photodetection. Dissipation and thermal noise are taken into account, as well as non unit quantum efficiency in the detection stage. We show that the IPS process, for a suitable choice of the involved parameters, improves teleportation fidelity and enhances nonlocal properties.Comment: 17 pages, 30 figure

    Noise versus chaos in a causal Fisher-Shannon plane

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    We revisit the Fisher-Shannon representation plane H×F{\mathcal H} \times {\mathcal F}, evaluated using the Bandt and Pompe recipe to assign a probability distribution to a time series. Several stochastic dynamical (noises with f−kf^{-k}, k≄0k \geq 0, power spectrum) and chaotic processes (27 chaotic maps) are analyzed so as to illustrate the approach. Our main achievement is uncovering the informational properties of the planar location.Comment: 6 pages, 1 figure. arXiv admin note: text overlap with arXiv:1401.213

    Motion of particles on a Four-Dimensional Asymptotically AdS Black Hole with Scalar Hair

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    Motivated by black hole solutions with matter fields outside their horizon, we study the effect of these matter fields in the motion of massless and massive particles. We consider as background a four-dimensional asymptotically AdS black hole with scalar hair. The geodesics are studied numerically and we discuss about the differences in the motion of particles between the four-dimensional asymptotically AdS black holes with scalar hair and their no-hair limit, that is, Schwarzschild AdS black holes. Mainly, we found that there are bounded orbits like planetary orbits in this background. However, the periods associated to circular orbits are modified by the presence of the scalar hair. Besides, we found that some classical tests such as perihelion precession, deflection of light and gravitational time delay have the standard value of general relativity plus a correction term coming from the cosmological constant and the scalar hair. Finally, we found a specific value of the parameter associated to the scalar hair, in order to explain the discrepancy between the theory and the observations, for the perihelion precession of Mercury and light deflection.Comment: 20 pages and 9 figures. arXiv admin note: text overlap with arXiv:1309.216

    Squeezed Fock state by inconclusive photon subtraction

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    We analyze in details the properties of the conditional state recently obtained by J. Wenger, et al. [Phys. Rev. Lett. {\bf 92}, 153601 (2004)] by means of inconclusive photon subtraction (IPS) on a squeezed vacuum state S(r)∣0⟩S(r)\ket{0}. The IPS process can be characterized by two parameters: the IPS transmissivity τ\tau and the photodetection quantum efficiency η\eta. We found that the conditional state approaches the squeezed Fock state S(r)∣1⟩S(r)\ket{1} when τ,η→1\tau,\eta \to 1, i.e., in the limit of single-photon subtraction. For non-unit IPS transmissivity and efficiency, the conditioned state remains close to the target state, {\em i.e.} shows a high fidelity for a wide range of experimental parameters. The nonclassicality of the conditional state is also investigated and a nonclassicality threshold on the IPS parameters is derived.Comment: 10 pages, 7 figure
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