6,618 research outputs found

    Double resonance of Raman transitions in a degenerate Fermi gas

    Get PDF
    We measure momentum-resolved Raman spectra of a spin-polarized degenerate Fermi gas of 173^{173}Yb atoms for a wide range of magnetic fields, where the atoms are irradiated by a pair of counterpropagating Raman laser beams as in the conventional spin-orbit coupling scheme. Double resonance of first- and second-order Raman transitions occurs at a certain magnetic field and the spectrum exhibits a doublet splitting for high laser intensities. The measured spectral splitting is quantitatively accounted for by the Autler-Townes effect. We show that our measurement results are consistent with the spinful band structure of a Fermi gas in the spatially oscillating effective magnetic field generated by the Raman laser fields.Comment: 7 pages, 6 figure

    Does the Electronic Medical Record (EMR) Adoption Matter? Exploring Patterns of EMR Implementation and its Impact on Hospital Performance

    Get PDF
    We aimed to explore the patterns of electronic medical records (EMR) adoption and its effects on hospital performance. We analyzed hospital-level panel data from 2008 to 2013 using Bayesian regression and the Naïve Bayes model. Our research analysis revealed 38 different adoption patterns for 1,919 hospitals that completed EMR implementation (having all of the four components) and 42 different investment patterns for 1,341 hospitals that could not complete the EMR implementation. We examined the hospitals’ EMR adoption patterns that were not completed; but predicted as completed using the Naïve Bayes model. Our results revealed that the hospitals that completed EMR adoption showed higher performance in terms of patient recommendation and net patient revenue than those that did not complete EMR adoption. More importantly, most of hospitals that observed as “not completed” but predicted as “completed” showed lower performance in terms of patient recommendation as well as net patient revenue

    Optimal Harvesting for an Age-Spatial-Structured Population Dynamic Model with External Mortality

    Get PDF
    We study an optimal harvesting for a nonlinear age-spatial-structured population dynamic model, where the dynamic system contains an external mortality rate depending on the total population size. The total mortality consists of two types: the natural, and external mortality and the external mortality reflects the effects of external environmental causes. We prove the existence and uniqueness of solutions for the population dynamic model. We also derive a sufficient condition for optimal harvesting and some necessary conditions for optimality in an optimal control problem relating to the population dynamic model. The results may be applied to an optimal harvesting for some realistic biological models

    Quantization of virtual Grothendieck rings and their structure including quantum cluster algebras

    Full text link
    The quantum Grothendieck ring of a certain category of finite-dimensional modules over a quantum loop algebra associated with a complex finite-dimensional simple Lie algebra g\mathfrak{g} has a quantum cluster algebra structure of skew-symmetric type. Partly motivated by a search of a ring corresponding to a quantum cluster algebra of {\em skew-symmetrizable} type, the quantum {\em virtual} Grothendieck ring, denoted by Kq(g)\mathfrak{K}_q(\mathfrak{g}), is recently introduced by Kashiwara--Oh \cite{KO23} as a subring of the quantum torus based on the (q,t)(q,t)-Cartan matrix specialized at q=1q=1. In this paper, we prove that Kq(g)\mathfrak{K}_q(\mathfrak{g}) indeed has a quantum cluster algebra structure of skew-symmetrizable type. This task essentially involves constructing distinguished bases of Kq(g)\mathfrak{K}_q(\mathfrak{g}) that will be used to make cluster variables and generalizing the quantum TT-system associated with Kirillov--Reshetikhin modules to establish a quantum exchange relation of cluster variables. Furthermore, these distinguished bases naturally fit into the paradigm of Kazhdan--Lusztig theory and our study of these bases leads to some conjectures on quantum positivity and qq-commutativity

    The seeded growth of graphene

    Get PDF
    In this paper, we demonstrate the seeded growth of graphene under a plasma chemical vapor deposition condition. First, we fabricate graphene nanopowders (~5 nm) by ball-milling commercial multi-wall carbon nanotubes. The graphene nanoparticles were subsequently subject to a direct current plasma generated in a 100 Torr 10%CH(4) - 90%H(2) gas mixture. The plasma growth enlarged, over one hour, the nuclei to graphene sheets larger than one hundred nm(2) in area. Characterization by electron and X-ray diffraction, high-resolution transmission electron microscopy images provide evidence for the presence of monolayer graphene sheets

    Description of the Diadegma fenestrale (Hymenoptera: Ichneumonidae: Campopleginae) Attacking the Potato Tuber Moth, Phthorimaea operculella (Lep.: Gelechiidae) New to Korea

    Get PDF
    Diadegma fenestrale is known as a parasitoid of the potato tuber moth, Phthorimaea operculella. The potato tuber moth, Phthorimaea operculella (Zeller) is one of the most destructive pest of potatoes. Also, we found this species attacking the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae). Ratio of parasitism is 20-30% and cocoon of lepidopteran was parasitic ichneumonid species after 3 days. This species and the genus Diadegma are recorded for the first time from Korea. In this paper, description of the parasitoid and photographs of the diagnostic characteristics are provided
    corecore