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Teleneurology clinics for polyneuropathy: a pilot study.
INTRODUCTION:Polyneuropathy (PN) is a common condition with significant morbidity. We developed tele-polyneuropathy (tele-PN) clinics to improve access to neurology and increase guideline-concordant PN care. This article describes the mixed-methods evaluation of pilot tele-PN clinics at three community sites within the Greater Los Angeles VA Healthcare System. METHODS:For the first 25 patients (48 scheduled visits), we recorded the duration of the tele-PN visit and exam; the performance on three guideline-concordant care indicators (PN screening labs, opiate reduction, physical therapy for falls); and patient-satisfaction scores. We elicited comments about the tele-PN clinic from patients and the clinical team. We combined descriptive statistics with qualitative themes to determine the feasibility and acceptability of the tele-PN clinics. RESULTS:The average tele-PN encounter and exam times were 28.5 and 9.1 min, respectively. PN screening lab completion increased from 80 to 100%. Opiate freedom improved from 68 to 88%. Physical therapy for patients with recent falls increased from 58 to 100%. The tele-PN clinic was preferred for follow-up over in-person clinics in 86% of cases. Convenience was paramount to the clinic's success, saving an average of 231 min per patient in round-trip travel. The medical team's caring and collaborative spirit received high praise. While the clinic's efficiency was equal or superior to in-person care, the limited treatment options for PN and the small clinical exam space are areas for improvement. CONCLUSION:In this pilot, we were able to efficiently see and examine patients remotely, promote guideline-concordant PN care, and provide a high-satisfaction encounter
Comparing Post-Newtonian and Numerical-Relativity Precession Dynamics
Binary black-hole systems are expected to be important sources of
gravitational waves for upcoming gravitational-wave detectors. If the spins are
not colinear with each other or with the orbital angular momentum, these
systems exhibit complicated precession dynamics that are imprinted on the
gravitational waveform. We develop a new procedure to match the precession
dynamics computed by post-Newtonian (PN) theory to those of numerical binary
black-hole simulations in full general relativity. For numerical relativity NR)
simulations lasting approximately two precession cycles, we find that the PN
and NR predictions for the directions of the orbital angular momentum and the
spins agree to better than with NR during the inspiral,
increasing to near merger. Nutation of the orbital plane on the
orbital time-scale agrees well between NR and PN, whereas nutation of the spin
direction shows qualitatively different behavior in PN and NR. We also examine
how the PN equations for precession and orbital-phase evolution converge with
PN order, and we quantify the impact of various choices for handling partially
known PN terms
Radio Planetary Nebulae in the Small Magellanic Cloud
We present ten new radio continuum (RC) detections at catalogued planetary
nebula (PN) positions in the Small Magellanic Cloud (SMC): SMPS6, LIN 41, LIN
142, SMP S13, SMP S14, SMP S16, J18, SMP S18, SMP S19 and SMP S22.
Additionally, six SMC radio PNe previously detected, LIN 45, SMP S11, SMPS17,
LIN321, LIN339 and SMPS24 are also investigated (re-observed) here making up a
population of 16 radio detections of catalogued PNe in the SMC. These 16 radio
detections represent ~15 % of the total catalogued PN population in the SMC. We
show that six of these objects have characteristics that suggest that they are
PN mimics: LIN 41, LIN 45, SMP S11, LIN 142, LIN 321 and LIN 339. We also
present our results for the surface brightness - PN radius relation
({\Sigma}-D) of the SMC radio PN population. These are consistent with previous
SMC and LMC PN measurements of the ({\Sigma}-D) relation.Comment: Accepted for publication in Astrophysics and Space Scienc
The role of planets in shaping planetary nebulae
In 1997 Soker laid out a framework for understanding the formation and
shaping of planetary nebulae (PN). Starting from the assumption that
non-spherical PN cannot be formed by single stars, he linked PN morphologies to
the binary mechanisms that may have formed them, basing these connections
almost entirely on observational arguments. In light of the last decade of
discovery in the field of PN, we revise this framework, which, although
simplistic, can still serve as a benchmark against which to test theories of PN
origin and shaping. Within the framework, we revisit the role of planets in
shaping PN. Soker invoked a planetary role in shaping PN because there are not
enough close binaries to shape the large fraction of non-spherical PN. In this
paper we adopt a model whereby only ~20% of all 1-8 solar mass stars make a PN.
This reduces the need for planetary shaping. Through a propagation of
percentages argument, and starting from the assumption that planets can only
shape mildly elliptical PN, we conclude, like in Soker, that ~20% of all PN
were shaped via planetary and other substellar interactions but we add that
this corresponds to only ~5% of all 1-8 solar mass stars. This may be in line
with findings of planets around main sequence stars. PN shaping by planets is
made plausible by the recent discovery of planets that have survived
interactions with red giant branch (RGB) stars. Finally, we conclude that of
the ~80% of 1-8 solar mass stars that do not make a PN, about one quarter do
not even ascend the AGB due to interactions with stellar and substellar
companions, while three quarters ascend the AGB but do not make a PN. Once
these stars leave the AGB they evolve normally and can be confused with
post-RGB, extreme horizontal branch stars. We propose tests to identify them.Comment: 23 pages, accepted by PAS
Equations of motion for the mass centers in a scalar theory of gravitation
A scalar theory of gravitation with a preferred reference frame (PRF) is
considered, that accounts for special relativity and reduces to it if the
gravitational field cancels. The gravitating system consists of a finite number
of perfect-fluid bodies. An " asymptotic " post-Newtonian (PN) approximation
scheme is used, allowing an explicit weak-field limit with all fields expanded.
Exact mass centers are defined and their exact equations of motion are derived.
The PN expansion of these equations is obtained: the zero-order equations are
those of Newtonian gravity (NG), and the equations for the first-order (PN)
corrections depend linearly on the PN fields. For PN corrections to the motion
of the mass centers, especially in the solar system, one may assume "
very-well-separated " rigidly moving bodies with spherical self-fields of the
zero-order approximation. The PN corrections reduce then to a time integration
and include spin effects, which might be significant. It is shown that the
Newtonian masses are not correct zero-order masses for the PN calculations. An
algorithm is proposed, in order to minimize the residual and to assess the
velocity in the PRF.Comment: Post-Script, 32 page
Quantum Transport Characteristics of Lateral pn-Junction of Single Layer TiS3
Using density functional theory and nonequilibrium Greens functions-based
methods we investigated the electronic and transport properties of monolayer
TiS3 pn-junction. We constructed a lateral pn-junction in monolayer TiS3 by
using Li and F adatoms. An applied bias voltage caused significant variability
in the electronic and transport properties of the TiS3 pn-junction. In
addition, spin dependent current-voltage characteristics of the constructed
TiS3 pn-junction were analyzed. Important device characteristics were found
such as negative differential resistance and rectifying diode behaviors for
spin-polarized currents in the TiS3 pn-junction. These prominent conduction
properties of TiS3 pn-junction offer remarkable opportunities for the design of
nanoelectronic devices based on a recently synthesized single-layered material
Planetary Nebula Surveys: Past, Present and Future
In this review we cover the detection, identification and astrophysical
importance of planetary nebulae (PN). The legacy of the historic Perek &
Kohoutek and Acker et al. catalogues is briefly covered before highlighting the
more recent but significant progress in PN discoveries in our Galaxy and the
Magellanic Clouds. We place particular emphasis on the major MASH and the IPHAS
catalogues, which, over the last decade alone, have essentially doubled
Galactic and LMC PN numbers. We then discuss the increasing role and importance
that multi-wavelength data is playing in both the detection of candidate PN and
the elimination of PN mimics that have seriously biased previous PN
compilations. The prospects for future surveys and current efforts and
prospects for PN detections in external galaxies are briefly discussed due to
their value both as cosmic distance indicators and as kinematical probes of
galaxies and dark matter properties.Comment: 8 pages, 1 figure, Proceedings of the Asymmetric Planetary Nebula V
Conference (Invited Review, Lake District, England, June 2010
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