14,074 research outputs found
Extra Corporeal Membrane Oxygenation (ECMO) review of a lifesaving technology
Extra Corporeal Membrane Oxygenation (ECMO) indications and usage has strikingly progressed over the last 20 years; it has become essential tool in the care of adults and children with severe cardiac and pulmonary dysfunction refractory to conventional management. In this article we will provide a review of ECMO development, clinical indications, patients' management, options and cannulations techniques, complications, outcomes, and the appropriate strategy of organ management while on ECMO
Simulation and detection of Dirac fermions with cold atoms in an optical lattice
We propose an experimental scheme to simulate and observe relativistic Dirac
fermions with cold atoms in a hexagonal optical lattice. By controlling the
lattice anisotropy, one can realize both massive and massless Dirac fermions
and observe the phase transition between them. Through explicit calculations,
we show that both the Bragg spectroscopy and the atomic density profile in a
trap can be used to demonstrate the Dirac fermions and the associated phase
transition.Comment: 4 pages; Published versio
Comparisons of housing price risks between first-time buyer and former owner-occupier markets in England
This study employs housing data from the nine main regions of
England and from overall England to compare the volatility risks
of housing prices for the first-time buyer (FTB) and former owneroccupier (FOO) markets. This study collects data from February
2012 to March 2020 to assess the volatility characteristics of housing prices in these two markets in each region of England.
Additionally, the effect of interest rate shocks and the wealth
effect of the stock market on these two markets are observed.
The results reveal that for most regions, the FTB market has
higher housing price volatility risks compared with the FOO market. Additionally, the FTB market is more easily affected by interest rate shocks and the wealth effect. In contrast to FOOs, FTBs
are generally younger and less wealthy. If FTBs are facing a market with higher housing price risk, especially when the overall
economy is affected by a shock (such as the European Debt Crisis
or the COVID-19 pandemic), the response of the FTB housing
market is greater; then the government must pay special attention when implementing policies that interfere with the market
since these policies would particularly affect the welfare of FTBs
Bethe ansatz for an AdS/CFT open spin chain with non-diagonal boundaries
We consider the integrable open-chain transfer matrix corresponding to a Y=0
brane at one boundary, and a Y_theta=0 brane (rotated with the respect to the
former by an angle theta) at the other boundary. We determine the exact
eigenvalues of this transfer matrix in terms of solutions of a corresponding
set of Bethe equations.Comment: 25 pages; v2: reference added; v3: minor revisions, form accepted by
journa
Use of extracorporeal membranous oxygenator in transcatheter aortic valve replacement
The superiority of transcatheter aortic valve replacement (TAVR) compared with medical therapy for patients with aortic stenosis (AS) who are not suitable candidates for surgery had been proven. Cardiopulmonary bypass (CPB) is rarely used in TAVR. Reports of early use of extracorporeal membranous oxygenator (ECMO) have promising outcomes. ECMO offers the option of cardiac support rescue in case of intraoperative hemodynamic instability and can be instituted in advance when hemodynamic instability is expected. Here we review the English literature about the use of ECMO in TAVR procedures, and discuss the indications and rationale for its use as well as its advantages
A Bayesian measurement error model for two-channel cell-based RNAi data with replicates
RNA interference (RNAi) is an endogenous cellular process in which small
double-stranded RNAs lead to the destruction of mRNAs with complementary
nucleoside sequence. With the production of RNAi libraries, large-scale RNAi
screening in human cells can be conducted to identify unknown genes involved in
a biological pathway. One challenge researchers face is how to deal with the
multiple testing issue and the related false positive rate (FDR) and false
negative rate (FNR). This paper proposes a Bayesian hierarchical measurement
error model for the analysis of data from a two-channel RNAi high-throughput
experiment with replicates, in which both the activity of a particular
biological pathway and cell viability are monitored and the goal is to identify
short hair-pin RNAs (shRNAs) that affect the pathway activity without affecting
cell activity. Simulation studies demonstrate the flexibility and robustness of
the Bayesian method and the benefits of having replicates in the experiment.
This method is illustrated through analyzing the data from a RNAi
high-throughput screening that searches for cellular factors affecting HCV
replication without affecting cell viability; comparisons of the results from
this HCV study and some of those reported in the literature are included.Comment: Published in at http://dx.doi.org/10.1214/11-AOAS496 the Annals of
Applied Statistics (http://www.imstat.org/aoas/) by the Institute of
Mathematical Statistics (http://www.imstat.org
Entanglement, subsystem particle numbers and topology in free fermion systems
We study the relationship between bipartite entanglement, subsystem particle
number and topology in a half-filled free fermion system. It is proposed that
the spin-projected particle numbers can distinguish the quantum spin Hall state
from other states, and can be used to establish a new topological index for the
system. Furthermore, we apply the new topological invariant to a disordered
system and show that a topological phase transition occurs when the disorder
strength is increased beyond a critical value. It is also shown that the
subsystem particle number fluctuation displays behavior very similar to that of
the entanglement entropy. This provides a lower-bound estimation for the
entanglement entropy, which can be utilized to obtain an estimate of the
entanglement entropy experimentally.Comment: 14 pages, 6 figure
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