14,737 research outputs found
Reducing Bias from Choice Experiments Estimates in the Demand for Recreation
In valuing the demand for recreation, the literature has grown from using revealed preference methods to applying stated preference methods, namely contingent valuation and choice modelling. Recent attempts have merged revealed and stated preference data to exploit the strengths of both sources of data. We use contingent behaviour and choice experiments data to show that, with choice experiments exercises, when respondents are asked to choose which improvement programme they prefer for a site with recreational opportunities, failing to consider the information explaining the number of visits that respondents intend to take to a recreational site under each hypothetical programme leads to biased coefficients estimates in the models for the choice experiments data.travel cost, contingent behaviour, choice experiments, revealed preferences, stated preferences, Environmental Economics and Policy, Q51, Q26,
Is Droxidopa Safe and Effective in Reducing Symptoms of Neurogenic Orthostatic Hypotension?
Objective: The objective of this selective EBM review is to determine whether or not droxidopa is safe and effective in reducing the symptoms of neurogenic orthostatic hypotension.
Study Design: Systemic review of three English-language primary studies, conducted in 2014 or later.
Data Sources: Three double-blind, randomized trials comparing the safety and efficacy of droxidopa to placebo in patients with diagnosed neurogenic orthostatic hypotension, found via PubMed in peer-reviewed journals.
Outcomes Measured: Improvement of symptoms was measured utilizing patient responses to the Orthostatic Hypotension Questionnaire (OHQ), which consists of a six item Orthostatic Hypotension Symptom Assessment (OSHA) and the four item Orthostatic Hypotension Daily Activity Scale (OHDAS), each measured on a 1-10 scale. Also utilized was the patient-rated Clinical Global Impression (CGI) severity and improvement 7-point scales. Safety was measured through incidence of adverse effects during the randomized trial.
Results: Biaggioni, et al, exhibited 46% of droxidopa recipients describing themselves as much or very much improved according to CGI ratings, compared to 27.5% of those receiving placebo, although with a p-score of 0.384. Hauser, et al, exhibited mean improvement in OSHA item 1 at week 1 as 2.3 for droxidopa, compared to 1.3 in the control group, with a p-value of 0.018. Kaufmann, et al, exhibited improvement of greater than 3 units in composite OHQ score in 27.2% of droxidopa recipients compared to 11.4% of placebo recipients, with a p score of 0.016. Numbers needed to harm were presented for each studied, obtained through measurement of adverse effects of experiment vs control during randomized trial, and consisted of -13 in Biaggioni, et al, 38 in Hauser, et al, and 28 in Kaufmann, et al.
Conclusions: These results indicate that droxidopa showed statistical improvement in symptoms in two studies and numerical improvement in another, in addition to being relatively well tolerated. However, the difference in end points measured in each studies and inconsistencies in study design prevent any strong conclusion, and further study is required
On local boundary CFT and non-local CFT on the boundary
The holographic relation between local boundary conformal quantum field
theories (BCFT) and their non-local boundary restrictions is reviewed, and
non-vacuum BCFT's, whose existence was conjectured previously, are constructed.Comment: 16 pages. Contribution to "Rigorous Quantum Field Theory", Symposium
in honour of J. Bros, Paris, July 2004. Based on joint work math-ph/0405067
with R. Long
Very high energy gamma-ray follow-up observations of novae and dwarf novae with the MAGIC telescopes
In the last few years the Fermi-LAT instrument has detected GeV gamma-ray
emission from several novae. Such GeV emission can be interpreted in terms of
inverse Compton emission from electrons accelerated in the shock or in terms of
emission from hadrons accelerated in the same conditions. The latter might
reach much higher energies and could produce a second component in the
gamma-ray spectrum at TeV energies. We perform follow-up observations of
selected novae and dwarf novae in search of the second component in TeV energy
gamma rays. This can shed light on the acceleration process of leptons and
hadrons in nova explosions. We have performed observations with the MAGIC
telescopes of 3 sources, a symbiotic nova YY Her, a dwarf nova ASASSN-13ax and
a classical nova V339 Del, shortly after their outbursts. We did not detect TeV
gamma-ray emission from any of the objects observed. The TeV upper limits from
MAGIC observations and the GeV detection by Fermi constrain the acceleration
parameters for electrons and hadrons.Comment: Proceedings of the 34th International Cosmic Ray Conference, 30 July-
6 August, 2015, The Hague, The Netherlands. The content of this submission is
similar to our paper in the Fermi Symposium of novae observations with MAGIC,
which appeared as arXiv:1502.05853. arXiv admin note: substantial text
overlap with arXiv:1502.0585
Charged sectors, spin and statistics in quantum field theory on curved spacetimes
The first part of this paper extends the Doplicher-Haag-Roberts theory of
superselection sectors to quantum field theory on arbitrary globally hyperbolic
spacetimes. The statistics of a superselection sector may be defined as in flat
spacetime and each charge has a conjugate charge when the spacetime possesses
non-compact Cauchy surfaces. In this case, the field net and the gauge group
can be constructed as in Minkowski spacetime.
The second part of this paper derives spin-statistics theorems on spacetimes
with appropriate symmetries. Two situations are considered: First, if the
spacetime has a bifurcate Killing horizon, as is the case in the presence of
black holes, then restricting the observables to the Killing horizon together
with "modular covariance" for the Killing flow yields a conformally covariant
quantum field theory on the circle and a conformal spin-statistics theorem for
charged sectors localizable on the Killing horizon. Secondly, if the spacetime
has a rotation and PT symmetry like the Schwarzschild-Kruskal black holes,
"geometric modular action" of the rotational symmetry leads to a
spin-statistics theorem for charged covariant sectors where the spin is defined
via the SU(2)-covering of the spatial rotation group SO(3).Comment: latex2e, 73 page
On intermediate subfactors of Goodman-de la Harpe-Jones subfactors
In this paper we present a conjecture on intermediate subfactors which is a
generalization of Wall's conjecture from the theory of finite groups. Motivated
by this conjecture, we determine all intermediate subfactors of
Goodman-Harpe-Jones subfactors, and as a result we verify that
Goodman-Harpe-Jones subfactors verify our conjecture. Our result also gives a
negative answer to a question motivated by a conjecture of
Aschbacher-Guralnick.Comment: To appear in Comm. Math. Phy
Constraints on Lorentz Invariance Violation from Fermi-Large Area Telescope Observations of Gamma-Ray Bursts
We analyze the MeV/GeV emission from four bright Gamma-Ray Bursts (GRBs)
observed by the Fermi-Large Area Telescope to produce robust, stringent
constraints on a dependence of the speed of light in vacuo on the photon energy
(vacuum dispersion), a form of Lorentz invariance violation (LIV) allowed by
some Quantum Gravity (QG) theories. First, we use three different and
complementary techniques to constrain the total degree of dispersion observed
in the data. Additionally, using a maximally conservative set of assumptions on
possible source-intrinsic spectral-evolution effects, we constrain any vacuum
dispersion solely attributed to LIV. We then derive limits on the "QG energy
scale" (the energy scale that LIV-inducing QG effects become important, E_QG)
and the coefficients of the Standard Model Extension. For the subluminal case
(where high energy photons propagate more slowly than lower energy photons) and
without taking into account any source-intrinsic dispersion, our most stringent
limits (at 95% CL) are obtained from GRB090510 and are E_{QG,1}>7.6 times the
Planck energy (E_Pl) and E_{QG,2}>1.3 x 10^11 GeV for linear and quadratic
leading order LIV-induced vacuum dispersion, respectively. These limits improve
the latest constraints by Fermi and H.E.S.S. by a factor of ~2. Our results
disfavor any class of models requiring E_{QG,1} \lesssim E_Pl.Comment: Accepted for publication by Physical Review
Lobotomia prĂ©-frontal. Resultados clĂnicos em hospital privado
Escola Paulista de Medicina Instituto Paulista Serviço de PsiquiatriaHospital de JuqueriSecção de Higiene Mental Escolar Serviço de Neuro-Psiquiatria do Instituto PaulistaUNIFESP, EPM, Instituto Paulista Serviço de PsiquiatriaSciEL
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