16,946,329 research outputs found
Reproductive outcomes following induced abortion : a national register-based cohort study in Scotland
PMID: 22869092 [PubMed] Free full textPeer reviewedPreprin
Identifying acne treatment uncertainties via a James Lind Alliance Priority Setting Partnership
Objectives: The Acne Priority Setting Partnership
(PSP) was set up to identify and rank treatment
uncertainties by bringing together people with acne,
and professionals providing care within and beyond the
National Health Service (NHS).
Setting: The UK with international participation.
Participants: Teenagers and adults with acne,
parents, partners, nurses, clinicians, pharmacists,
private practitioners.
Methods: Treatment uncertainties were collected via
separate online harvesting surveys, embedded within the
PSP website, for patients and professionals. A wide
variety of approaches were used to promote the surveys
to stakeholder groups with a particular emphasis on
teenagers and young adults. Survey submissions were
collated using keywords and verified as uncertainties by
appraising existing evidence. The 30 most popular
themes were ranked via weighted scores from an online
vote. At a priority setting workshop, patients and
professionals discussed the 18 highest-scoring questions
from the vote, and reached consensus on the top 10.
Results: In the harvesting survey, 2310 people,
including 652 professionals and 1456 patients (58%
aged 24 y or younger), made submissions containing at
least one research question. After checking for relevance
and rephrasing, a total of 6255 questions were collated
into themes. Valid votes ranking the 30 most common
themes were obtained from 2807 participants. The top 10
uncertainties prioritised at the workshop were largely
focused on management strategies, optimum use of
common prescription medications and the role of nondrug
based interventions. More female than male patients
took part in the harvesting surveys and vote. A wider
range of uncertainties were provided by patients
compared to professionals.
Conclusions: Engaging teenagers and young adults in
priority setting is achievable using a variety of
promotional methods. The top 10 uncertainties reveal an
extensive knowledge gap about widely used interventions
and the relative merits of drug versus non-drug based
treatments in acne management
Complete 1-Loop Calculation of the T-violating D-Parameter in Neutron Decay in the MSSM
We investigate the violation of time reversal invariance in the decay of the
free neutron in the framework of the Minimal Supersymmetric Standard Model
(MSSM). The coefficient of the triple product of the neutron spin and the
momenta of electron and neutrino, the so called D parameter, is computed at one
loop order including all diagrams. We find that D is mainly sensitive to the
trilinear A coupling in the squark sector and to the phase of the coefficient
\mu which mixes the two Higgs superfields. The maximal MSSM contribution using
parameters still allowed by experiment is however at D \approx 10^{-7}, while
QED final state interactions give a value of D_{fsi} = - 2.3 * 10^{-5}.
Explicit expressions for all relevant diagrams are given in an Appendix.Comment: 24 pages, 14 figures; Improved scanning of parameter space leads to
some numerical change, but the basic conclusion remains unchange
A Systematic Study of Neutrino Mixing and CP Violation from Lepton Mass Matrices with Six Texture Zeros
We present a systematic study of 400 combinations of the charged lepton and
neutrino mass matrices with six vanishing entries or texture zeros. Only 24 of
them, which can be classified into a few distinct categories, are found to be
compatible with current neutrino oscillation data at the level. A
peculiar feature of the lepton mass matrices in each category is that they have
the same phenomenological consequences. Taking account of a simple seesaw
scenario for six parallel patterns of the charged lepton and Dirac neutrino
mass matrices with six zeros, we show that it is possible to fit the
experimental data at or below the level. In particular, the maximal
atmospheric neutrino mixing can be reconciled with a strong neutrino mass
hierarchy in the seesaw case. Numerical predictions are also obtained for the
neutrino mass spectrum, flavor mixing angles, CP-violating phases and effective
masses of the tritium beta decay and the neutrinoless double beta decay.Comment: 35 pages, 15 figures, minor change
Quantum mechanics in curved space-time
In this paper, the principles of the general relativity are used to formulate
quantum wave equations for spin-0 and spin-1/2 particles. More specifically,
the equations are worked in a Schwarzschild-like metric. As a test, the
hydrogen atom spectrum is calculated. A comparison of the calculated spectrum
with the numerical data of the deuterium energy levels shows a significant
improvement of the accord, and the deviations are almost five times smaller
then the ones obtained with the Dirac theory. The implications of the theory
considering the strong interactions are also discussed
Sum rules for total hadronic widths of light mesons and rectilineal stitch of the masses on the complex plane
Mass formulae for light meson multiplets derived by means of exotic
commutator technique are written for complex masses and considered as complex
mass sum rules (CMSR). The real parts of the (CMSR) give the well known mass
formulae for real masses (Gell-Mann--Okubo, Schwinger and Ideal Mixing ones)
and the imaginary parts of CMSR give appropriate sum rules for the total
hadronic widths - width sum rules (WSR). Most of the observed meson nonets
satisfy the Schwinger mass formula (S nonets). The CMSR predict for S nonet
that the points form the rectilinear stitch (RS) on the complex
mass plane. For low-mass nonets WSR are strongly violated due to
``kinematical'' suppression of the particle decays, but the violation decreases
as the mass icreases and disappears above . The slope of
the RS is not predicted, but the data show that it is negative for all S nonets
and its numerical values are concentrated in the vicinity of the value -0.5. If
is known for a nonet, we can evaluate ``kinematical'' suppressions of its
individual particles. The masses and the widths of the S nonet mesons submit to
some rules of ordering which matter in understanding the properties of the
nonet. We give the table of the S nonets indicating masses, widths, mass and
width orderings. We show also mass-width diagrams for them. We suggest to
recognize a few multiplets as degenerate octets. In Appendix we analyze the
nonets of mesons.Comment: 20 pages, 3 figures; title and discussion expanded; additional text;
final version accepted for publication in EPJ
Fock States of Flavor Neutrinos are Unphysical
It is shown that it is possible to construct an infinity of Fock spaces of
flavor neutrinos depending on arbitrary unphysical mass parameters, in
agreement with the theory of Blasone and Vitiello in the version proposed by
Fujii, Habe and Yabuki. However, we show that these flavor neutrino Fock spaces
are clever mathematical constructs without physical relevance, because the
hypothesis that neutrinos produced or detected in charged-current weak
interaction processes are described by flavor neutrino Fock states implies that
measurable quantities depend on the arbitrary unphysical flavor neutrino mass
parameters.Comment: 11 page
Flavor changing neutral currents from lepton and B decays in the two Higgs doublet model
Constraints on the whole spectrum of lepton flavor violating vertices are
shown in the context of the standard two Higgs doublet model. The vertex
involving the mixing is much more constrained than the others, and
the decays proportional to such vertex are usually very supressed. On the other
hand, bounds on the quark sector are obtained from leptonic decays of the
mesons and from . We emphasize that
although the mixing restricts severely the
mixing vertex, the upper bound for this vertex could still give a sizeable
contribution to the decay respect to the standard
model contribution, from which we see that such vertex could still play a role
in the phenomenology.Comment: 9 pages, 2 figures, LaTeX2e. Minor typos corrected. References added
and corrected. Introduction change
A New Application of the Gursey and Radicati Mass Formula
We study the spin- and flavour- dependent SU(6) violations in the baryon
spectrum by means of a G\"ursey Radicati mass formula. The average energy of
each SU(6)-multiplet is described using the SU(6) invariant interaction given
by a hypercentral potential containing a linear and a hypercoulomb term. We
show that the non strange and strange baryon masses are in general fairly well
reproduced and moreover that the G\"ursey Radicati formula holds in a
satisfactory way also for the excited states up to 2 GeV. The coefficients of
the G\"ursey Radicati SU(6) breaking part obtained by the fit of the
three-quark spectrum can be used to evaluate in first approximation the
splitting within multiplets also for exotic baryon systems.Comment: 9 pages, 2 figures, 2 table, submitted to Eur. Phys. J.
Bosonic corrections to the effective leptonic weak mixing angle at the two-loop level
Details of the recent calculation of the two-loop bosonic corrections to the
effective leptonic weak mixing angle are presented. In particular, the
expansion in the difference of the W and Z boson masses is studied and some of
the master integrals needed are given in analytic form.Comment: 5 pages, 4 figures, to appear in the proceedings of the 7th
International Symposium on Radiative Corrections (RADCOR05), Shonan Village,
Japan, 200
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