1,489 research outputs found
The Controversies and Difficulties of Diagnosing Primary Ciliary Dyskinesia
We welcome the correspondence from Lavie and Amirav (1), highlighting the difficulties diagnosing primary ciliary dyskinesia (PCD) and the role of high-speed video analysis (HSVA). As members of the European Respiratory Society (ERS) PCD Diagnostic Task Force (2) and/or large PCD Centres, we agree that HSVA has an important role that is not recognized by the American Thoracic Society (ATS) PCD Diagnostic Guideline (3). This risks a large proportion of false-negative “missed” diagnoses and a sizable number of false-positive cases; we make additional important observations.</div
The Relation Between Galaxy ISM and Circumgalactic OVI Gas Kinematics Derived from Observations and CDM Simulations
We present the first galaxy-OVI absorption kinematic study for 20 absorption
systems (EW>0.1~{\AA}) associated with isolated galaxies (0.150.55) that
have accurate redshifts and rotation curves obtained using Keck/ESI. Our sample
is split into two azimuthal angle bins: major axis () and
minor axis (). OVI absorption along the galaxy major axis is
not correlated with galaxy rotation kinematics, with only 1/10 systems that
could be explained with rotation/accretion models. This is in contrast to
co-rotation commonly observed for MgII absorption. OVI along the minor axis
could be modeled by accelerating outflows but only for small opening angles,
while the majority of the OVI is decelerating. Along both axes, stacked OVI
profiles reside at the galaxy systemic velocity with the absorption kinematics
spanning the entire dynamical range of their galaxies. The OVI found in AMR
cosmological simulations exists within filaments and in halos of ~50 kpc
surrounding galaxies. Simulations show that major axis OVI gas inflows along
filaments and decelerates as it approaches the galaxy while increasing in its
level of co-rotation. Minor axis outflows in the simulations are effective
within 50-75 kpc beyond that they decelerate and fall back onto the galaxy.
Although the simulations show clear OVI kinematic signatures they are not
directly comparable to observations. When we compare kinematic signatures
integrated through the entire simulated galaxy halo we find that these
signatures are washed out due to full velocity distribution of OVI throughout
the halo. We conclude that OVI alone does not serve as a useful kinematic
indicator of gas accretion, outflows or star-formation and likely best probes
the halo virial temperature.Comment: 24 pages, 21 figures, 4 tables. Accepted to ApJ on November 14, 201
Effects of Noise, Correlations and errors in the preparation of initial states in Quantum Simulations
In principle a quantum system could be used to simulate another quantum
system. The purpose of such a simulation would be to obtain information about
problems which cannot be simulated with a classical computer due to the
exponential increase of the Hilbert space with the size of the system and which
cannot be measured or controlled in an actual experiment. The system will
interact with the surrounding environment, with the other particles in the
system and be implemented using imperfect controls making it subject to noise.
It has been suggested that noise does not need to be controlled to the same
extent as it must be for general quantum computing. However the effects of
noise in quantum simulations and how to treat them are not completely
understood. In this paper we study an existing quantum algorithm for the
one-dimensional Fano-Anderson model to be simulated using a liquid-state NMR
device. We calculate the evolution of different initial states in the original
model, and then we add interacting spins to simulate a more realistic
situation. We find that states which are entangled with their environment, and
sometimes correlated but not necessarily entangled have an evolution which is
described by maps which are not completely positive. We discuss the conditions
for this to occur and also the implications.Comment: Revtex 4-1, 14 pages, 21 figures, version 2 has typos corrected and
acknowledgement adde
Exercise-based cardiac rehabilitation for adult patients with an implantable cardioverter defibrillator
Review question:
We reviewed the benefits and harms of exercise-based cardiac rehabilitation programmes in adults who have been treated with an implantable cardioverter defibrillator from any cause.
Background:
An implantable cardioverter defibrillator is a very effective device that prevents sudden cardiac death. This is done by the use of either antitachycardia pacing, high-voltage shock therapy, or both. In spite of the potential mortality benefits, patients may also experience a negative impact on their health-related quality of life, increased readmission to hospital and healthcare facilities, loss of productivity and employment earnings, and increased morbidity and mortality. Exercise-based cardiac rehabilitation may benefit patients with an implantable cardioverter defibrillator.
Study characteristics:
We searched for randomised controlled trials (experiments in which participants are randomly allocated to an experimental intervention compared with a control intervention) that investigated exercise-based interventions compared with no exercise intervention control. We found eight trials published from 2004 to 2017 with a total of 1730 participants. Two trials did not report on funding and one trial reported funding from industry. The evidence is current to 30 August 2018.
Key results:
The review showed no evidence of an impact on the risk of death, harmful side effects or having antitachycardia pacing or shock therapy when comparing the exercise intervention to the control. There was also little or no evidence of a difference on health-related quality of life. However, there was an improvement in exercise capacity in favour of the exercise group.
Quality of the evidence:
The quality of the evidence ranged from moderate to very low for all outcomes. The number of events was low, it was possible for people in the trials to know to which intervention group they were randomised, the reporting of the results was not complete in some trials, and for some outcomes, the results varied across trials. These considerations limited our confidence in the overall results of the review.
Conclusion:
Further adequately powered and well-conducted randomised trials are needed to assess the impact of exercise-based cardiac rehabilitation in adults with an implantable cardioverter defibrillator
The role of demonstrator familiarity and language cues on infant imitation from television
An imitation procedure was used to investigate the impact of demonstrator familiarity and language cues on infant learning from television. Eighteen-month-old infants watched two pre-recorded videos showing an adult demonstrating a sequence of actions with two sets of stimuli. Infants' familiarity with the demonstrator and the language used during the demonstration varied as a function of experimental condition. Immediately after watching each video, infants' ability to reproduce the target actions was assessed. A highly familiar demonstrator did not enhance infants' performance. However, the addition of a narrative, developed from mothers' naturalistic description of the event, facilitated learning from an unfamiliar demonstrator. We propose that the differential effect of demonstrator familiarity and language cues may reflect the infants' ability to distinguish between important and less important aspects in a learning situation. (C) 2010 Elsevier Inc. All rights reserved
Evaluation of alternative solvents in common amide coupling reactions : replacement of dichloromethane and N,N-dimethylformamide
A range of alternative solvents have been evaluated within amidation reactions employing common coupling reagents with a view to identifying suitable replacements for dichloromethane and N,N-dimethylformamid
Detailed statistical analysis plan for the Danish Palliative care trial (DanPaCT)
Acknowledgements We wish to thank the students who sent out the questionnaires, who entered and compared all data, help with data management, made material blind to the investigators, and were/will be outcome assessors of interventions given. They were: Nicla Rohde Christensen, Ellen Lundorff, Marc Klee Olsen, Charlotte Lund Rasmussen, and Nete Skjødt. This work was funded by the Tryg Foundation [journal number 7-10-0838A] and the Danish Cancer Society [journal number R16-A695]. Other than funding the trial, the funding body had no role in the design, conduct, analysis, or reporting of the present trial.Peer reviewedPublisher PD
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