We study excitonic states of an atomic impurity in a Fermi gas, i.e., bound states consisting of the impurity and a hole. Previous studies considered bound states of the impurity with particles from the Fermi sea where the holes formed only part of the particle-hole dressing. Within a two-channel model, we find that, for a wide range of parameters, excitonic states are not ground but metastable...

Over the past 20 years there have been many changes to the primary and secondary educational system that have impacted students, teachers, and post-secondary institutions across the United States of America. One of the most important is the large number of standardized tests students are required to take to show adequate performance in school. Students think differently because they are taught ...

this study seeks to examine how a company can select the best intermediary for its marketing channels with minimum of criteria and time. a theoretical framework is proposed based on the most important tasks of intermediary and the criteria to measure them. there are four basic tasks and thirty criteria in three independent levels. subsequently, an exploratory case study in iranian food industry...

We propose a method for the theoretical investigation of polymer translocation through composite pore structures possessing arbitrarily specified geometries. The proposed method accounts for possible reverse chain motions at the interface between the constituent parts of a composite pore. As an illustration of our method, we study polymer translocation between two spherical compartments connect...

We consider a multiuser (MU) multiple-input multiple-output (MIMO) time-division duplexing (TDD) system in which the base station (BS) is equipped with a large number of antennas for communicating with single-antenna mobile users. In such a system the BS has to estimate the channel state information (CSI) that includes large-scale fading coefficients (LSFCs) and small-scale fading coefficients ...

PURPOSE The objective of this study was to determine whether a sodium phased array would improve sodium breast MRI at 3 T. The secondary objective was to create acceptable proton images with the sodium phased array in place. METHODS A novel composite array for combined proton/sodium 3 T breast MRI is compared with a coil with a single proton and sodium channel. The composite array consists of...

In recent years, although the China government has carried out some serious investigation and effort to shut down the indigenous coke-production, it has not achieved effective control. The main image TM754 (red, green, blue) false color composite of Shanxi province in northern China was chosen as the study area in this paper. The indigenous coke-production sites are regions which appear red and...

A composite drag control (CDC) combining the opposition (OC) and spanwise opposed wall-jet forcing (SOJF) methods is investigated. maximum reduction of about 33% obtained for CDC -- much higher than that produced by either individual method (namely, 19% SOJF 23% OC). Flow analysis shows can take advantage both OC to better suppress producing near-wall turbulent structures --vortices streaks. Ou...

We introduce an interlayer coherent composite Fermi liquid for nu = 1/2 + 1/2 bilayers, in which interlayer Coulomb repulsion drives exciton condensation of composite fermions. As a result, composite fermions propagate coherently between layers--even though electrons do not--and form bonding and antibonding Fermi seas. This phase is compressible with respect to symmetric currents but quantum Ha...