1,975 research outputs found
Large System Analysis of Downlink MISO-NOMA System via Regularized Zero-Forcing Precoding with Imperfect CSIT
This letter studies the multiple-input single-output (MISO) non-orthogonal multiple-access (NOMA) downlink using regularized zero-forcing (RZF) precoding with imperfect channel state information (CSI). We first propose a new user scheduling scheme based on imperfect CSI and a model to characterize the channel correlation between the weak and strong users. Then we derive an approximate expression of the ergodic sum-rate using large-system random matrix theory. This approximation permits us to derive the optimal power allocation scheme that satisfies the rate requirement of the weak users. Simulation results are presented to confirm the accuracy of the approximation and reveal the relationships between the ergodic sum-rate, the channel correlation, and other system parameters
Navigating oxygen deprivation: Liver transcriptomic responses of the red eared slider turtle to environmental anoxia
The best facultative anaerobes among vertebrates are members of the genera Trachemys (pond slider turtles) and Chrysemys (painted turtles), and are able to survive without oxygen for up to 12 to 18 weeks at ∼3 °C. In this study, we utilized RNAseq to profile the transcriptomic changes that take place in response to 20 hrs of anoxia at 5 °C in the liver of the red eared slide turtle (Trachemys scripta elegans). Sequencing reads were obtained from at least 18,169 different genes and represented a minimum 49x coverage of the C. picta bellii exome. A total of 3,105 genes showed statistically significant changes in gene expression between the two animal groups, of which 971 also exhibited a fold change equal to or greater than 50% of control normoxic values. This study also highlights a number of anoxia-responsive molecular pathways that are may be important to navigating anoxia survival. These pathways were enriched in mRNA found to significantly increase in response to anoxia and included molecular processes such as DNA damage repair and metabolic reprogramming. For example, our results indicate that the anoxic turtle may utilize succinate metabolism to yield a molecule of GTP in addition to the two molecules that results from lactate production, and agrees with other established models of anoxia tolera
On Traversable Lorentzian Wormholes in the Vacuum Low Energy Effective String Theory in Einstein and Jordan Frames
Three new classes (II-IV) of solutions of the vacuum low energy effective
string theory in four dimensions are derived. Wormhole solutions are
investigated in those solutions including the class I case both in the Einstein
and in the Jordan (string) frame. It turns out that, of the eight classes of
solutions investigated (four in the Einstein frame and four in the
corresponding string frame), massive Lorentzian traversable wormholes exist in
five classes. Nontrivial massless limit exists only in class I Einstein frame
solution while none at all exists in the string frame. An investigation of test
scalar charge motion in the class I solution in the two frames is carried out
by using the Plebanski-Sawicki theorem. A curious consequence is that the
motion around the extremal zero (Keplerian) mass configuration leads, as a
result of scalar-scalar interaction, to a new hypothetical "mass" that confines
test scalar charges in bound orbits, but does not interact with neutral test
particles.Comment: 18 page
Defect and anisotropic gap induced quasi-one-dimensional modulation of local density of states in YBaCuO
Motivated by recent angle-resolved photoemission spectroscopy (ARPES)
measurement that superconducting YBaCuO (YBCO) exhibits a
-symmetry gap, we show possible quasi-one-dimensional
modulations of local density of states in YBCO. These aniostropic gap and
defect induced stripe structures are most conspicuous at higher biases and
arise due to the nesting effect associated with a Fermi liquid. Observation of
these spectra by scanning tunneling microscopy (STM) would unify the picture
among STM, ARPES, and inelastic neutron scattering for YBCO.Comment: 4 pages, 4 figure
Time and lexicographic preferences in the valuation of EQ-5D-Y with time trade-off methodology
In the valuation of EQ-5D-Y-3L, adult respondents are asked to complete composite time trade-off (cTTO) tasks for a 10-year-old child. Earlier work has shown that cTTO utilities elicited in such a child perspective are generally higher than when adults take their own perspective. We explore how differences in time preference in child and adult perspectives could explain this effect. Furthermore, as cTTO valuation in a child perspective involves explicit consideration of immediate death for a child, we also consider how cTTO utilities could be affected by decision-makers lexicographically avoiding death in children. We report the results of an experiment in which 219 respondents valued 5 health states in both adult and child perspectives with either a standard cTTO or a lead-time TTO only approach, in which immediate death is less focal. Time preferences were measured in both perspectives. Our results suggest that utilities were lower when lead-time TTO, rather than cTTO, was used. We find large heterogeneity in time preference in both perspectives, with predominantly negative time preference. The influence of time preferences on utilities, however, was small, and correcting for time preferences did not reduce differences between utilities elicited in both perspectives. Surprisingly, we found more evidence for differences in utilities between adult and child perspectives when lead-time TTO was used. Overall, these results suggest that time and lexicographic preferences affect time trade-off valuation in child and adult perspectives, but are not the explanation for differences between these perspectives. We discuss the implications of our findings for EQ-5D-Y-3L valuation
Notes on Theories
The cosmological models based on teleparallel gravity with nonzero torsion
are considered. To investigate the evolution of this theory, we consider the
phase-space analysis of the theory. It shows when the tension scalar can
be written as an inverse function of where
and , the system is an autonomous one. Furthermore,the
phase analysis is given out. We perform the dynamical
analysis for the models and particularly. We find that the universe will
settle into de-Sitter phase for both models. And we have examined the evolution
behavior of the power law form in the plane.Comment: 13 pages, 2 figure
EXPLORATIVE VERSUS EXPLOITATIVE ALLIANCES—EVIDENCE FROM THE GLASS INDUSTRY IN CHINA
This study empirically delineates the nature of explorative and exploitative alliances, examines how they affect product and process innovations, and investigates how such effects vary in different contexts. Using a sample of 220 Chinese firms in the glass industry, we find that explorative alliances have a stronger effect on both product and process innovations than exploitative alliances. Product and process innovations are positively related to both market and efficiency performance and environmental turbulence enhances the effect of product and process innovations. Our findings provide implications on how to choose between explorative and exploitative alliances relative to the alliance objectives and firm resources and environmental contexts
EXPLORATIVE VERSUS EXPLOITATIVE ALLIANCES—EVIDENCE FROM THE GLASS INDUSTRY IN CHINA
This study empirically delineates the nature of explorative and exploitative alliances, examines how they affect product and process innovations, and investigates how such effects vary in different contexts. Using a sample of 220 Chinese firms in the glass industry, we find that explorative alliances have a stronger effect on both product and process innovations than exploitative alliances. Product and process innovations are positively related to both market and efficiency performance and environmental turbulence enhances the effect of product and process innovations. Our findings provide implications on how to choose between explorative and exploitative alliances relative to the alliance objectives and firm resources and environmental contexts
Phase transitions and ordering of confined dipolar fluids
We apply a modified mean-field density functional theory to determine the
phase behavior of Stockmayer fluids in slitlike pores formed by two walls with
identical substrate potentials. Based on the Carnahan-Starling equation of
state, a fundamental-measure theory is employed to incorporate the effects of
short-ranged hard sphere - like correlations while the long-ranged
contributions to the fluid interaction potential are treated perturbatively.
The liquid-vapor, ferromagnetic liquid - vapor, and ferromagnetic liquid -
isotropic liquid first-order phase separations are investigated. The local
orientational structure of the anisotropic and inhomogeneous ferromagnetic
liquid phase is also studied. We discuss how the phase diagrams are shifted and
distorted upon varying the pore width.Comment: 15 pages including 8 figure
Disappearance of Ensemble-Averaged Josephson Current in Dirty SNS Junctions of d-wave Superconductors
We discuss the Josephson current in superconductor / dirty normal conductor /
superconductor junctions, where the superconductors have pairing
symmetry. The low-temperature behavior of the Josephson current depends on the
orientation angle between the crystalline axis and the normal of the junction
interface. We show that the ensemble-averaged Josephson current vanishes when
the orientation angle is and the normal conductor is in the diffusive
transport regime. The -wave pairing symmetry is responsible for
this fact.Comment: 8 pages, 5 figure
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