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Assessing plantar sensation in the foot using the FOot Roughness Discrimination Test (FoRDT™): a reliability and validity study in stroke
BACKGROUND: The foot sole represents a sensory dynamometric map and is essential for balance and gait control. Sensory impairments are common, yet often difficult to quantify in neurological conditions, particularly stroke. A functionally oriented and quantifiable assessment, the Foot Roughness Discrimination Test (FoRDT™), was developed to address these shortcomings. OBJECTIVE: To evaluate inter- and intra-rater reliability, convergent and discriminant validity of the Foot Roughness Discrimination Test (FoRDT™). DESIGN: Test-retest design. SETTING: Hospital Outpatient. PARTICIPANTS: Thirty-two people with stroke (mean age 70) at least 3 months after stroke, and 32 healthy, age-matched controls (mean age 70). MAIN OUTCOME MEASURES: Roughness discrimination thresholds were quantified utilising acrylic foot plates, laser-cut to produce graded spatial gratings. Stroke participants were tested on three occasions, and by two different raters. Inter- and intra-rater reliability and agreement were evaluated with Intraclass Correlation Coefficients and Bland-Altman plots. Convergent validity was evaluated through Spearman rank correlation coefficients (rho) between the FoRDT™ and the Erasmus modified Nottingham Sensory Assessment (EmNSA). RESULTS: Intra- and inter rater reliability and agreement were excellent (ICC =.86 (95% CI .72-.92) and .90 (95% CI .76 -.96)). Discriminant validity was demonstrated through significant differences in FoRDT™ between stroke and control participants (p.05). CONCLUSIONS: This simple and functionally oriented test of plantar sensation is reliable, valid and clinically feasible for use in an ambulatory, chronic stroke and elderly population. It offers clinicians and researchers a sensitive and robust sensory measure and may further support the evaluation of rehabilitation targeting foot sensation. This article is protected by copyright. All rights reserved
Lorentz Invariance Violation in Modified Gravity
We consider an environmentally dependent violation of Lorentz invariance in
scalar-tensor models of modified gravity where General Relativity is retrieved
locally thanks to a screening mechanism. We find that fermions have a modified
dispersion relation and would go faster than light in an anisotropic and
space-dependent way along the scalar field lines of force. Phenomenologically,
these models are tightly restricted by the amount of Cerenkov radiation emitted
by the superluminal particles, a constraint which is only satisfied by
chameleons. Measuring the speed of neutrinos emitted radially from the surface
of the earth and observed on the other side of the earth would probe the scalar
field profile of modified gravity models in dense environments. We argue that
the test of the equivalence principle provided by the Lunar ranging experiment
implies that a deviation from the speed of light, for natural values of the
coupling scale between the scalar field and fermions, would be below detectable
levels, unless gravity is modified by camouflaged chameleons where the field
normalisation is environmentally dependent.Comment: 8 pages, extended discussio
Minimally invasive presacral approach for revision of an Axial Lumbar Interbody Fusion rod due to fall-related lumbosacral instability: a case report
<p>Abstract</p> <p>Introduction</p> <p>The purpose of this study was to describe procedural details of a minimally invasive presacral approach for revision of an L5-S1 Axial Lumbar Interbody Fusion rod.</p> <p>Case presentation</p> <p>A 70-year-old Caucasian man presented to our facility with marked thoracolumbar scoliosis, osteoarthritic changes characterized by high-grade osteophytes, and significant intervertebral disc collapse and calcification. Our patient required crutches during ambulation and reported intractable axial and radicular pain. Multi-level reconstruction of L1-4 was accomplished with extreme lateral interbody fusion, although focal lumbosacral symptoms persisted due to disc space collapse at L5-S1.</p> <p>Lumbosacral interbody distraction and stabilization was achieved four weeks later with the Axial Lumbar Interbody Fusion System (TranS1 Inc., Wilmington, NC, USA) and rod implantation via an axial presacral approach.</p> <p>Despite symptom resolution following this procedure, our patient suffered a fall six weeks postoperatively with direct sacral impaction resulting in symptom recurrence and loss of L5-S1 distraction. Following seven months of unsuccessful conservative care, a revision of the Axial Lumbar Interbody Fusion rod was performed that utilized the same presacral approach and used a larger diameter implant. Minimal adhesions were encountered upon presacral re-entry. A precise operative trajectory to the base of the previously implanted rod was achieved using fluoroscopic guidance. Surgical removal of the implant was successful with minimal bone resection required. A larger diameter Axial Lumbar Interbody Fusion rod was then implanted and joint distraction was re-established. The radicular symptoms resolved following revision surgery and our patient was ambulating without assistance on post-operative day one. No adverse events were reported.</p> <p>Conclusions</p> <p>The Axial Lumbar Interbody Fusion distraction rod may be revised and replaced with a larger diameter rod using the same presacral approach.</p
Edoxaban: an update on the new oral direct factor Xa inhibitor.
Edoxaban is a once-daily oral anticoagulant that rapidly and selectively inhibits factor Xa in a concentration-dependent manner. This review describes the extensive clinical development program of edoxaban, including phase III studies in patients with non-valvular atrial fibrillation (NVAF) and symptomatic venous thromboembolism (VTE). The ENGAGE AF-TIMI 48 study (N = 21,105; mean CHADS2 score 2.8) compared edoxaban 60 mg once daily (high-dose regimen) and edoxaban 30 mg once daily (low-dose regimen) with dose-adjusted warfarin [international normalized ratio (INR) 2.0-3.0] and found that both regimens were non-inferior to warfarin in the prevention of stroke and systemic embolism in patients with NVAF. Both edoxaban regimens also provided significant reductions in the risk of hemorrhagic stroke, cardiovascular mortality, major bleeding and intracranial bleeding. The Hokusai-VTE study (N = 8,292) in patients with symptomatic VTE had a flexible treatment duration of 3-12 months and found that following initial heparin, edoxaban 60 mg once daily was non-inferior to dose-adjusted warfarin (INR 2.0-3.0) for the prevention of recurrent VTE, and also had a significantly lower risk of bleeding events. Both studies randomized patients at moderate-to-high risk of thromboembolic events and were further designed to simulate routine clinical practice as much as possible, with edoxaban dose reduction (halving dose) at randomisation or during the study if required, a frequently monitored and well-controlled warfarin group, a well-monitored transition period at study end and a flexible treatment duration in Hokusai-VTE. Given the phase III results obtained, once-daily edoxaban may soon be a key addition to the range of antithrombotic treatment options
Localized Supersoft Supersymmetry Breaking
We consider supersymmetry breaking models in which the MSSM is extended to
include an additional chiral adjoint field for each gauge group with which the
the MSSM gauginos acquire Dirac masses. We investigate a framework in which the
Standard Model gauge fields propagate in the bulk of a warped extra dimension
while quarks and leptons are localized on the ultraviolet brane. The adjoint
fields are localized on the infrared brane, where supersymmetry is broken in a
hidden sector. This setup naturally suppresses potentially large flavor
violating effects, while allowing perturbative gauge coupling unification under
SU(5) to be realized. The Standard Model superpartner masses exhibit a
supersoft spectrum. Since the soft scalar masses are generated at very low
scales of order the gaugino masses these models are significantly less
fine-tuned than other supersymmetric models. The LSP in this class of models is
the gravitino, while the NLSP is the stau. We show that this theory has an
approximate R symmetry under which the gauginos are charged. This symmetry
allows several possibilities for experimentally distinguishing the Dirac nature
of the gauginos.Comment: 23 pages, 2 figure
The Chemical Compositions of Non-Variable Red and Blue Field Horizontal Branch Stars
We present a new detailed abundance study of field red horizontal branch
(RHB) and blue horizontal branch (BHB) non-variable stars. High resolution and
high S/N echelle spectra of 11 RHB and 12 BHB were obtained with the McDonald
2.7 m telescope, and the RHB sample was augmented by reanalysis of spectra of
25 stars from a recent survey. We derived stellar atmospheric parameters based
on spectroscopic constraints, and computed relative abundance ratios for 24
species of 19 elements. The species include Si II and Ca II, which have not
been previously studied in RHB and BHB (Teff < 9000 K) stars. The abundance
ratios are generally consistent with those of similar-metallicity field stars
in different evolutionary stages. We estimated the masses of the RHB and BHB
stars by comparing their Teff--log g positions with HB model evolutionary
tracks. The mass distribution suggests that our program stars possess masses of
~0.5 Msun. Finally, we compared the temperature distributions of field RHB and
BHB stars with field RR Lyraes in the metallicity range -0.8 >~ [Fe/H] >~ -2.5.
This yielded effective temperatures estimates of 5900K and 7400 K for the red
and blue edges of the RR Lyrae instability strip.Comment: Accepted to A
Gravitational Leptogenesis and Neutrino Mass Limit
Recently Davoudiasl {\it et al} \cite{steinhardt} have introduced a new type
of interaction between the Ricci scalar and the baryon current ,
and proposed a mechanism for baryogenesis, the
gravitational baryogenesis. Generally, however, vanishes in
the radiation dominated era. In this paper we consider a generalized form of
their interaction, and study again the possibility
of gravitational baryo(lepto)genesis. Taking , we will show
that does not vanish and the
required baryon number asymmetry can be {\it naturally} generated in the early
universe.Comment: 4 page
Unified model for the gamma-ray emission of supernova remnants
Shocks of supernova remnants (SNRs) are important (and perhaps the dominant)
agents for production of the Galactic cosmic rays. Recent -ray
observations of several SNRs have made this case more compelling. However,
these broadband high-energy measurements also reveal a variety of spectral
shape demanding more comprehensive modeling of emissions from SNRs. According
to the locally observed fluxes of cosmic ray protons and electrons, the
electron-to-proton number ratio is known to be about 1%. Assuming such a ratio
is universal for all SNRs and identical spectral shape for all kinds of
accelerated particles, we propose a unified model that ascribes the distinct
-ray spectra of different SNRs to variations of the medium density and
the spectral difference between cosmic ray electrons and protons observed at
Earth to transport effects. For low density environments, the -ray
emission is inverse-Compton dominated. For high density environments like
systems of high-energy particles interacting with molecular clouds, the
-ray emission is -decay dominated. The model predicts a hadronic
origin of -ray emission from very old remnants interacting mostly with
molecular clouds and a leptonic origin for intermediate age remnants whose
shocks propagate in a low density environment created by their progenitors via
e.g., strong stellar winds. These results can be regarded as evidence in
support of the SNR-origin of the Galactic cosmic rays.Comment: 7 pages (two-column), 5 figures, 1 table; discussion added; accepted
by Ap
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