350 research outputs found
ERA Critical Issues Report: Report of the Forward Visions on the European Research Area (VERA) project
Regge and Okamoto symmetries
We will relate the surprising Regge symmetry of the Racah-Wigner 6j symbols
to the surprising Okamoto symmetry of the Painleve VI differential equation.
This then presents the opportunity to give a conceptual derivation of the Regge
symmetry, as the representation theoretic analogue of the author's previous
derivation of the Okamoto symmetry.
[The resulting derivation is quite simple, so it would be surprising if it
has not been previously observed. Any references would be appreciated!]Comment: 14 page
Categorical geometric skew Howe duality
We categorify the R-matrix isomorphism between tensor products of minuscule
representations of U_q(sl(n)) by constructing an equivalence between the
derived categories of coherent sheaves on the corresponding convolution
products in the affine Grassmannian. The main step in the construction is a
categorification of representations of U_q(sl(2)) which are related to
representations of U_q(sl(n)) by quantum skew Howe duality. The resulting
equivalence is part of the program of algebro-geometric categorification of
Reshitikhin-Turaev tangle invariants developed by the first two authors.Comment: 31 page
Atlas of the OMERACT Heel Enthesitis MRI Scoring System (HEMRIS)
Objective: Assessment of enthesitis, a key feature in spondyloarthritis (SpA) and psoriatic arthritis (PsA), using objective and sensitive methods is pivotal in clinical trials. MRI allows detection of both soft tissue and intra-osseous changes of enthesitis. This article presents an atlas for the Outcome Measures in Rheumatology (OMERACT) Heel Enthesitis Magnetic Resonance ImagingMRI Scoring System (HEMRIS).
Methods: Following a preliminary selection of potential examples of each grade, as per HEMRIS definitions, the images along with detailed definitions and reader rules were discussed at web-based, interactive meetings between the members of the OMERACT MRI in Arthritis Working Group.
Results: Reference images of each grade of the MRI features to be assessed using HEMRIS, along with reader rules and recommended MRI sequences are depicted.
Conclusion: The presented reference images can be used to guide scoring Achilles tendon and plantar fascia (plantar aponeurosis) enthesitis according to the OMERACT HEMRIS in clinical trials and cohorts in which MRI enthesitis is used as an outcome
Treatment of Truncal Incompetence and Varicose Veins with a Single Administration of a New Polidocanol Endovenous Microfoam Preparation Improves Symptoms and Appearance
ObjectiveThis multicenter, parallel group study was designed to determine if a single administration of ≤15 mL of pharmaceutical-grade polidocanol endovenous microfoam (PEM, now approved in the United States as Varithena [polidocanol injectable foam], BTG International Ltd.) could alleviate symptoms and improve appearance of varicose veins in a typical population of patients with moderate to very severe symptoms of superficial venous incompetence and visible varicosities of the great saphenous vein (GSV) system.MethodsThe primary endpoint was patient-reported venous symptom improvement measured by change from baseline to Week 8 in 7-day average VVSymQ score. Co-secondary endpoints measured improvement in appearance of visible varicose veins from baseline to Week 8, as measured by the Independent Photography Review–Visible Varicose Veins (IPR-V3) and Patient Self-assessment of Visible Varicose Veins (PA-V3) scores. Patients were randomized to five groups: PEM 0.125% (control), 0.5%, 1%, 2%, or placebo. Adverse events (AEs) were recorded at each study visit. Tertiary endpoints measured duplex ultrasound response, changes in venous clinical severity score, and the modified Venous Insufficiency Epidemiological and Economic Study–Quality of Life/Symptoms.ResultsAt Week 8, VVSymQ scores for the pooled PEM group (0.5% + 1% + 2%; p < .0001) and individual dose concentrations (p < .001) were significantly superior to placebo. Mean changes from baseline to Week 8 in IPR-V3 and PA-V3 scores were significantly greater for pooled PEM than for placebo (p < .0001). Most AEs were mild and resolved without sequelae. No pulmonary emboli were reported.ConclusionsThis study demonstrated that a single administration of up to 15 mL of PEM is a safe, effective, and convenient treatment for the symptoms of superficial venous incompetence and the appearance of visible varicosities of the GSV system. Doses of 0.5%, 1%, and 2% PEM appear to have an acceptable risk-benefit ratio
Meromorphic tensor equivalence for Yangians and quantum loop algebras
Let be a complex semisimple Lie algebra, and , the corresponding Yangian and quantum loop algebra,
with deformation parameters related by . When is not a
rational number, we constructed in arXiv:1310.7318 a faithful functor
from the category of finite-dimensional representations of to those of . The functor is governed by the
additive difference equations defined by the commuting fields of the Yangian,
and restricts to an equivalence on a subcategory of
defined by choosing a branch of the logarithm. In this paper, we construct a
tensor structure on and show that, if , it yields an
equivalence of meromorphic braided tensor categories, when
and are endowed with the deformed Drinfeld coproducts and
the commutative part of the universal -matrix. This proves in particular the
Kohno-Drinfeld theorem for the abelian KZ equations defined by
. The tensor structure arises from the abelian KZ
equations defined by a appropriate regularisation of the commutative -matrix
of .Comment: Title changed, details added. 67 pages, 1 figure. Final version, to
appear in Publ. Math IHE
Displacement rate effect on the flexural properties of glass fiber reinforced polyurethane
Numerical Weather Prediction (NWP) and hybrid ARMA/ANN model to predict global radiation
We propose in this paper an original technique to predict global radiation
using a hybrid ARMA/ANN model and data issued from a numerical weather
prediction model (ALADIN). We particularly look at the Multi-Layer Perceptron.
After optimizing our architecture with ALADIN and endogenous data previously
made stationary and using an innovative pre-input layer selection method, we
combined it to an ARMA model from a rule based on the analysis of hourly data
series. This model has been used to forecast the hourly global radiation for
five places in Mediterranean area. Our technique outperforms classical models
for all the places. The nRMSE for our hybrid model ANN/ARMA is 14.9% compared
to 26.2% for the na\"ive persistence predictor. Note that in the stand alone
ANN case the nRMSE is 18.4%. Finally, in order to discuss the reliability of
the forecaster outputs, a complementary study concerning the confidence
interval of each prediction is proposedComment: Energy (2012)
Asymptotic equivalence of discretely observed diffusion processes and their Euler scheme: small variance case
This paper establishes the global asymptotic equivalence, in the sense of the
Le Cam -distance, between scalar diffusion models with unknown drift
function and small variance on the one side, and nonparametric autoregressive
models on the other side. The time horizon is kept fixed and both the cases
of discrete and continuous observation of the path are treated. We allow non
constant diffusion coefficient, bounded but possibly tending to zero. The
asymptotic equivalences are established by constructing explicit equivalence
mappings.Comment: 21 page
- …