73 research outputs found
Conformal properties of hypermultiplet actions in six dimensions
We consider scale-invariant interactions of 6D N=1 hypermultiplets with the
gauge multiplet. If the canonical dimension of the matter scalar field is
assumed to be 1, scale-invariant lagrangians involve higher derivatives in the
action. Though scale-invariant, all such lagrangians are not invariant with
respect to special conformal transformations and their superpartners. If the
scalar canonical dimension is assumed to be 2, conformal invariance holds at
the classical, but not at the quantum level.Comment: 14 pages, 1 figur
Renormalizable supersymmetric gauge theory in six dimensions
We construct and discuss a 6D supersymmetric gauge theory involving four
derivatives in the action. The theory involves a dimensionless coupling
constant and is renormalizable. At the tree level, it enjoys N = (1,0)
superconformal symmetry, but the latter is broken by quantum anomaly. Our study
should be considered as preparatory for seeking an extended version of this
theory which would hopefully preserve conformal symmetry at the full quantum
level and be ultraviolet-finite.Comment: 20 pages, 2 figures. An arithmetic error in the calculation of the
coefficient of the beta function is corrected. Its sign (corresponding to the
Landau zero situation) stays the same as in the earlier version
Low-energy structure of the even-A 96−104 Ru isotopes via g-factor measurements
The transient-field-perturbed angular correlation technique was used with Coulomb excitation in inverse kinematics to perform a systematic measurement of the g factors of the first excited 21+ states in the stable even-A isotopes Ru96-104. The measurements have been made relative to one another under matched kinematic conditions and include a measurement of g(21+)=+0.47(3) in Ru96
Interrupted time series study found mixed effects of the impact of the Bavarian smoke-free legislation on pregnancy outcomes
In 2007 the German government passed smoke-free legislation, leaving the details of implementation to the individual federal states. In January 2008 Bavaria implemented one of the strictest laws in Germany. We investigated its impact on pregnancy outcomes and applied an interrupted time series (ITS) study design to assess any changes in preterm birth, small for gestational age (primary outcomes), and low birth weight, stillbirth and very preterm birth. We included 1,236,992 singleton births, comprising 83,691 preterm births and 112,143 small for gestational age newborns. For most outcomes we observed unclear effects. For very preterm births, we found an immediate drop of 10.4% (95%CI − 15.8, − 4.6%; p = 0.0006) and a gradual decrease of 0.5% (95%CI − 0.7, − 0.2%, p = 0.0010) after implementation of the legislation. The majority of subgroup and sensitivity analyses confirm these results. Although we found no statistically significant effect of the Bavarian smoke-free legislation on most pregnancy outcomes, a substantial decrease in very preterm births was observed. We cannot rule out that despite our rigorous methods and robustness checks, design-inherent limitations of the ITS study as well as country-specific factors, such as the ambivalent German policy context have influenced our estimation of the effects of the legislation
PYTHIA 6.4 Physics and Manual
The PYTHIA program can be used to generate high-energy-physics `events', i.e.
sets of outgoing particles produced in the interactions between two incoming
particles. The objective is to provide as accurate as possible a representation
of event properties in a wide range of reactions, within and beyond the
Standard Model, with emphasis on those where strong interactions play a role,
directly or indirectly, and therefore multihadronic final states are produced.
The physics is then not understood well enough to give an exact description;
instead the program has to be based on a combination of analytical results and
various QCD-based models. This physics input is summarized here, for areas such
as hard subprocesses, initial- and final-state parton showers, underlying
events and beam remnants, fragmentation and decays, and much more. Furthermore,
extensive information is provided on all program elements: subroutines and
functions, switches and parameters, and particle and process data. This should
allow the user to tailor the generation task to the topics of interest.Comment: 576 pages, no figures, uses JHEP3.cls. The code and further
information may be found on the PYTHIA web page:
http://www.thep.lu.se/~torbjorn/Pythia.html Changes in version 2: Mistakenly
deleted section heading for "Physics Processes" reinserted, affecting section
numbering. Minor updates to take into account referee comments and new colour
reconnection option
Measurement of the partial widths of the Z into up- and down-type quarks
Using the entire OPAL LEP1 on-peak Z hadronic decay sample, Z -> qbarq gamma
decays were selected by tagging hadronic final states with isolated photon
candidates in the electromagnetic calorimeter. Combining the measured rates of
Z -> qbarq gamma decays with the total rate of hadronic Z decays permits the
simultaneous determination of the widths of the Z into up- and down-type
quarks. The values obtained, with total errors, were Gamma u = 300 ^{+19}_{-18}
MeV and Gamma d = 381 ^{+12}_{-12} MeV. The results are in good agreement with
the Standard Model expectation.Comment: 22 pages, 5 figures, Submitted to Phys. Letts.
Oncoplastic Breast Consortium consensus conference on nipple-sparing mastectomy
Purpose Indications for nipple-sparing mastectomy (NSM) have broadened to include the risk reducing setting and locally
advanced tumors, which resulted in a dramatic increase in the use of NSM. The Oncoplastic Breast Consortium consensus
conference on NSM and immediate reconstruction was held to address a variety of questions in clinical practice and research
based on published evidence and expert panel opinion.
Methods The panel consisted of 44 breast surgeons from 14 countries across four continents with a background in gynecology, general or reconstructive surgery and a practice dedicated to breast cancer, as well as a patient advocate. Panelists
presented evidence summaries relating to each topic for debate during the in-person consensus conference. The iterative
process in question development, voting, and wording of the recommendations followed the modified Delphi methodology.
Results Consensus recommendations were reached in 35, majority recommendations in 24, and no recommendations in the
remaining 12 questions. The panel acknowledged the need for standardization of various aspects of NSM and immediate
reconstruction. It endorsed several oncological contraindications to the preservation of the skin and nipple. Furthermore, it
recommended inclusion of patients in prospective registries and routine assessment of patient-reported outcomes. Considerable heterogeneity in breast reconstruction practice became obvious during the conference.
Conclusions In case of conflicting or missing evidence to guide treatment, the consensus conference revealed substantial
disagreement in expert panel opinion, which, among others, supports the need for a randomized trial to evaluate the safest
and most efficacious reconstruction techniques
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