4,250 research outputs found
Group polytope faces pursuit for recovery of block-sparse signals
This is the accepted version of the article. The final publication is available at link.springer.com. http://www.springerlink.com/content/e0r61416446277w0
Measured equation of invariance: a new concept in field computations
Numerical computations of frequency domain field problems or elliptical partial differential equations may be based on differential equations or integral equations. The new concept of field computation presented in this paper is based on the postulate of the existence of linear equations of the discretized nodal values of the fields, different from the conventional equations, but leading to the same solutions. The postulated equations are local and invariant to excitation. It is shown how the equations can be determined by a sequence ofPeer ReviewedPostprint (published version
Fermi super-Tonks-Girardeau state for attractive Fermi gases in an optical lattice
We demonstrate that a kind of highly excited state of strongly attractive
Hubbard model, named of Fermi super-Tonks-Girardeau state, can be realized in
the spin-1/2 Fermi optical lattice system by a sudden switch of interaction
from the strongly repulsive regime to the strongly attractive regime. In
contrast to the ground state of the attractive Hubbard model, such a state is
the lowest scattering state with no pairing between attractive fermions. With
the aid of Bethe-ansatz method, we calculate energies of both the Fermi
Tonks-Girardeau gas and the Fermi super-Tonks-Girardeau state of spin-1/2
ultracold fermions and show that both energies approach to the same limit as
the strength of the interaction goes to infinity. By exactly solving the quench
dynamics of the Hubbard model, we demonstrate that the Fermi
super-Tonks-Girardeau state can be transferred from the initial repulsive
ground state very efficiently. This allows the experimental study of properties
of Fermi super-Tonks-Girardeau gas in optical lattices.Comment: 7 pages, 7 figure
Conversion Disorder in a Depressed Patient: The Analysis of Paralysis
Patients presenting with neurologic and pseudoneurologic symptoms present both a diagnostic and treatment challenge. This case report describes the ER course of a man who presented with aphonia and paralysis, his medical clearance, transfer to the psychiatric ER and subsequent recovery. The history of conversion disorder and its characteristics are briefly reviewed, and the etiology of this patient\u27s symptoms and a discussion of effective treatment plans are discussed
Inhibition of arterial thrombosis: synergistic interaction between platelet IIb/IIIa receptor and tissue factor
Unsteady Full Annulus Simulations of a Transonic Axial Compressor Stage
Two recent research endeavors in turbomachinery at NASA Glenn Research Center have focused on compression system stall inception and compression system aerothermodynamic performance. Physical experiment and computational research are ongoing in support of these research objectives. TURBO, an unsteady, three-dimensional, Navier-Stokes computational fluid dynamics code commissioned and developed by NASA, has been utilized, enhanced, and validated in support of these endeavors. In the research which follows, TURBO is shown to accurately capture compression system flow range-from choke to stall inception-and also to accurately calculate fundamental aerothermodynamic performance parameters. Rigorous full-annulus calculations are performed to validate TURBO s ability to simulate the unstable, unsteady, chaotic stall inception process; as part of these efforts, full-annulus calculations are also performed at a condition approaching choke to further document TURBO s capabilities to compute aerothermodynamic performance data and support a NASA code assessment effort
The Effects of Antenatal Betamethasone on Late Preterm Infants
Administration of steroids to mothers expected to deliver in the late preterm period has previously been found to decrease neonatal respiratory morbidity. In this retrospective chart review, there were no significant differences between groups in the primary outcome of required respiratory support for the neonate, incidence of periventricular hemorrhage or neonatal death. However, this study found that their rate of hyperbilirubinemia, need for phototherapy, and NICU stays were longer than their counterparts whose mothers did not receive steroids or who only received one dose.These findings may provide support for future protocols directed to improve neonatal morbidity secondary to jaundice
Greenberger-Horne-Zeilinger nonlocality for continuous variable systems
As a development of our previous work, this paper is concerned with the
Greenberger-Horne-Zeilinger (GHZ) nonlocality for continuous variable cases.
The discussion is based on the introduction of a pseudospin operator, which has
the same algebra as the Pauli operator, for each of the modes of a light
field. Then the Bell-CHSH (Clauser, Horne, Shimony and Holt) inequality is
presented for the modes, each of which has a continuous degree of freedom.
Following Mermin's argument, it is demonstrated that for -mode
parity-entangled GHZ states (in an infinite-dimensional Hilbert space) of the
light field, the contradictions between quantum mechanics and local realism
grow exponentially with , similarly to the usual -spin cases.Comment: RevTEX; comments are welcomed; new version with minor change
Endowment effect in capuchin monkeys
In humans, the capacity for economically rational choice is constrained by a variety of preference biases: humans evaluate gambles relative to arbitrary reference points; weigh losses heavier than equally sized gains; and demand a higher price for owned goods than for equally preferred goods that are not yet owned. To date, however, fewer studies have examined the origins of these biases. Here, we review previous work demonstrating that human economic biases such as loss aversion and reference dependence are shared with an ancestrally related New World primate, the capuchin monkey (Cebus apella). We then examine whether capuchins display an endowment effect in a token-trading task. We identified pairs of treats (fruit discs versus cereal chunks) that were equally preferred by each monkey. When given a chance to trade away their owned fruit discs to obtain the equally valued cereal chunks (or vice versa), however, monkeys required a far greater compensation than the equally preferred treat. We show that these effects are not due to transaction costs or timing issues. These data suggest that biased preferences rely on cognitive systems that are more evolutionarily ancient than previously thought—and that common evolutionary ancestry shared by humans and capuchins may account for the occurrence of the endowment effect in both species
- …