17 research outputs found
FlexibleSUSY: Precise automated calculations in any BSM theory
FlexibleSUSY is a software package for various calculations in any model of
physics beyond the standard model (not just any supersymmetric model).
FlexibleSUSY can solve boundary value problems and uses this to find
parameters and calculate the Higgs and BSM
particle masses, as well as other observables. FlexibleSUSY is designed to be
adaptable, fast, precise and reliable. We describe FlexibleSUSY with particular
emphasis on recent developments and the state of the art Higgs mass
calculations it can perform. We also show some applications to illustrate how
it can be used to obtain interesting physics results with the highest precision
possible and with remarkable speed.Comment: 4 pages plus title page, 1 figure. Contribution to proceedings of
ICHEP 2018, the 39th International Conference on High Energy Physic
FlexibleDecay: An automated calculator of scalar decay widths
We present FlexibleDecay, a tool to calculate decays of scalars in a broad
class of BSM models. The tool aims for high precision particularly in the case
of Higgs boson decays. In the case of scalar and pseudoscalar Higgs boson
decays the known higher order SM QED, QCD and EW effects are taken into account
where possible. The program works in a modified scheme that
exhibits a decoupling property with respect to heavy BSM physics, with BSM
parameters themselves treated in the -scheme
allowing for an easy connection to high scale tests for, e.g., perturbativity
and vacuum stability, and the many observable calculations readily available in
programs. Pure BSM effects are taken into
account at the leading order, including all one-loop contributions to
loop-induced processes. The program is implemented as an extension to
FlexibleSUSY, which determines the mass spectrum for arbitrary BSM models, and
does not require any extra configuration from the user. We compare our
predictions for Higgs decays in the SM, singlet extended SM, type II THDM,
CMSSM and MRSSM, as well as for squark decays in the CMSSM against a selection
of publicly available tools. The numerical differences between our and other
programs are explained. The release of FlexibleDecay officially deprecates the
old effective couplings routines in FlexibleSUSY.Comment: 44 pages, 3 figures, 11 tables; version published in CP
Precision tools and models to narrow in on the 750 GeV diphoton resonance
The hints for a new resonance at 750 GeV from ATLAS and CMS have triggered a
significant amount of attention. Since the simplest extensions of the standard
model cannot accommodate the observation, many alternatives have been
considered to explain the excess. Here we focus on several proposed
renormalisable weakly-coupled models and revisit results given in the
literature. We point out that physically important subtleties are often missed
or neglected. To facilitate the study of the excess we have created a
collection of 40 model files, selected from recent literature, for the
Mathematica package SARAH. With SARAH one can generate files to perform
numerical studies using the tailor-made spectrum generators FlexibleSUSY and
SPheno. These have been extended to automatically include crucial higher order
corrections to the diphoton and digluon decay rates for both CP-even and CP-odd
scalars. Additionally, we have extended the UFO and CalcHep interfaces of
SARAH, to pass the precise information about the effective vertices from the
spectrum generator to a Monte-Carlo tool. Finally, as an example to demonstrate
the power of the entire setup, we present a new supersymmetric model that
accommodates the diphoton excess, explicitly demonstrating how a large width
can be obtained. We explicitly show several steps in detail to elucidate the
use of these public tools in the precision study of this model.Comment: 184 pages, 24 figures; model files available at
http://sarah.hepforge.org/Diphoton_Models.tar.gz; v2: added a few
clarifications and reference
Periprosthetic Joint Infection After Total Knee Arthroplasty With or Without Antibiotic Bone Cement.
IMPORTANCE
Despite increased use of antibiotic-loaded bone cement (ALBC) in joint arthroplasty over recent decades, current evidence for prophylactic use of ALBC to reduce risk of periprosthetic joint infection (PJI) is insufficient.
OBJECTIVE
To compare the rate of revision attributed to PJI following primary total knee arthroplasty (TKA) using ALBC vs plain bone cement.
DESIGN, SETTING, AND PARTICIPANTS
This international cohort study used data from 14 national or regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, New Zealand, Norway, Romania, Sweden, Switzerland, the Netherlands, the UK, and the US. The study included primary TKAs for osteoarthritis registered from January 1, 2010, to December 31, 2020, and followed-up until December 31, 2021. Data analysis was performed from April to September 2023.
EXPOSURE
Primary TKA with ALBC vs plain bone cement.
MAIN OUTCOMES AND MEASURES
The primary outcome was risk of 1-year revision for PJI. Using a distributed data network analysis method, data were harmonized, and a cumulative revision rate was calculated (1â-âKaplan-Meier), and Cox regression analyses were performed within the 10 registries using both cement types. A meta-analysis was then performed to combine all aggregated data and evaluate the risk of 1-year revision for PJI and all causes.
RESULTS
Among 2âŻ168âŻ924 TKAs included, 93% were performed with ALBC. Most TKAs were performed in female patients (59.5%) and patients aged 65 to 74 years (39.9%), fully cemented (92.2%), and in the 2015 to 2020 period (62.5%). All participating registries reported a cumulative 1-year revision rate for PJI of less than 1% following primary TKA with ALBC (range, 0.21%-0.80%) and with plain bone cement (range, 0.23%-0.70%). The meta-analyses based on adjusted Cox regression for 1âŻ917âŻ190 TKAs showed no statistically significant difference at 1 year in risk of revision for PJI (hazard rate ratio, 1.16; 95% CI, 0.89-1.52) or for all causes (hazard rate ratio, 1.12; 95% CI, 0.89-1.40) among TKAs performed with ALBC vs plain bone cement.
CONCLUSIONS AND RELEVANCE
In this study, the risk of revision for PJI was similar between ALBC and plain bone cement following primary TKA. Any additional costs of ALBC and its relative value in reducing revision risk should be considered in the context of the overall health care delivery system
The use of antibiotic-loaded bone cement and systemic antibiotic prophylactic use in 2,971,357 primary total knee arthroplasties from 2010 to 2020: an international register-based observational study among countries in Africa, Europe, North America, and Oceania.
BACKGROUND AND PURPOSE
Antibiotic-loaded bone cement (ALBC) and systemic antibiotic prophylaxis (SAP) have been used to reduce periprosthetic joint infection (PJI) rates. We investigated the use of ALBC and SAP in primary total knee arthroplasty (TKA).
PATIENTS AND METHODS
This observational study is based on 2,971,357 primary TKAs reported in 2010-2020 to national/regional joint arthroplasty registries in Australia, Denmark, Finland, Germany, Italy, the Netherlands, New Zealand, Norway, Romania, South Africa, Sweden, Switzerland, the UK, and the USA. Aggregate-level data on trends and types of bone cement, antibiotic agents, and doses and duration of SAP used was extracted from participating registries.
RESULTS
ALBC was used in 77% of the TKAs with variation ranging from 100% in Norway to 31% in the USA. Palacos R+G was the most common (62%) ALBC type used. The primary antibiotic used in ALBC was gentamicin (94%). Use of ALBC in combination with SAP was common practice (77%). Cefazolin was the most common (32%) SAP agent. The doses and duration of SAP used varied from one single preoperative dosage as standard practice in Bolzano, Italy (98%) to 1-day 4 doses in Norway (83% of the 40,709 TKAs reported to the Norwegian arthroplasty register).
CONCLUSION
The proportion of ALBC usage in primary TKA varies internationally, with gentamicin being the most common antibiotic. ALBC in combination with SAP was common practice, with cefazolin the most common SAP agent. The type of ALBC and type, dose, and duration of SAP varied among participating countries
Aspects of Eâ inspired supersymmetric models
Supersymmetry (SUSY) is currently one of the best motivated extensions of the Standard
Model (SM) of particle physics. Softly broken SUSY naturally stabilises the
electroweak scale against large quantum corrections, without the unnatural fine tuning
required in the SM. However, experimental searches for superpartners and the
observed 125 GeV Higgs mass now imply that large corrections again arise in the minimal
supersymmetric standard model (MSSM), reintroducing the need for fine tuning.
In this thesis, we study a class of non-minimal Eâ inspired SUSY models that
are partially motivated by solving these and other problems of the MSSM. A unified
Eâ gauge group at high energies is assumed to lead to a low-energy theory with one
or more additional U(1) gauge symmetries and extra matter content compared to the
MSSM. To facilitate the study of these and other Beyond the Standard Model theories,
we implement several extensions to existing automated tools, significantly improving
their capabilities and range of applicability.
In the simplest Eâ inspired models, additional contributions to the Higgs mass
reduce the need for large radiative corrections but introduce a new source of fine
tuning associated with a massive Z' boson. By considering several such models at low
energies, we show that experimental limits on the mass of this state imply a minimal
amount of fine tuning is required to reproduce the electroweak scale. The severity of
this fine tuning is also shown to depend strongly on the details of the gauge symmetry
breaking.
We next consider an alternative Eâ model with a single, exact custodial symmetry.
This custodial symmetry, combined with an automatically conserved matter parity,
implies the existence of two dark matter candidates in the model. We explore the
parameter spaces of constrained versions of this model and the MSSM in which one
dark matter candidate is a MSSM-like mixed bino-Higgsino or pure Higgsino state.
We find that the dark matter relic density may be reproduced while satisfying experimental
constraints, and that light exotics may be discoverable at the Large Hadron
Collider. We conclude by investigating the impacts of current and future direct detection
searches on the parameter spaces of both models.Thesis (Ph.D.) -- University of Adelaide, School of Physical Sciences, 201
Dynamic Bayesian Networks for Evaluation of Granger Causal Relationships in Climate Reanalyses
Abstract We apply a Bayesian structure learning approach to study interactions between global climate modes, so illustrating its use as a framework for developing processâbased diagnostics with which to evaluate climate models. Homogeneous dynamic Bayesian network models are constructed for time series of empirical indices diagnosing the activity of major tropical, Northern and Southern Hemisphere modes of climate variability in the NCEP/NCAR and JRAâ55 reanalyses. The resulting probabilistic graphical models are comparable to Granger causal analyses that have recently been advocated. Reversible jump Markov Chain Monte Carlo is employed to provide a quantification of the uncertainty associated with the selection of a single network structure. In general, the models fitted from the NCEP/NCAR reanalysis and the JRAâ55 reanalysis are found to exhibit broad agreement in terms of associations for which there is high posterior confidence. Differences between the two reanalyses are found that involve modes for which known biases are present or that may be attributed to seasonal effects, as well as for features that, while present in point estimates, have low overall posterior mass. We argue that the ability to incorporate such measures of confidence in structural features is a significant advantage provided by the Bayesian approach, as point estimates alone may understate the relevant uncertainties and yield less informative measures of differences between products when networkâbased approaches are used for model evaluation