We present an update of the global fit of the Standard Model electroweak sector to latest experimental results. We include new kinematic top quark and
W
boson mass measurements from the LHC, a
sin
2
...θ
eff
ℓ
result from the Tevatron, and a new evaluation of the hadronic contribution to
α
(
M
Z
2
)
. We present tests of the internal consistency of the electroweak Standard Model and updated numerical predictions of key observables. The electroweak data combined with measurements of the Higgs boson coupling strengths and flavour physics observables are used to constrain parameters of two-Higgs-doublet models.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
For a long time, global fits of the electroweak sector of the standard model (SM) have been used to exploit measurements of electroweak precision observables at lepton colliders (LEP, SLC), together ...with measurements at hadron colliders (Tevatron, LHC) and accurate theoretical predictions at multi-loop level, to constrain free parameters of the SM, such as the Higgs and top masses. Today, all fundamental SM parameters entering these fits are experimentally determined, including information on the Higgs couplings, and the global fits are used as powerful tools to assess the validity of the theory and to constrain scenarios for new physics. Future measurements at the Large Hadron Collider (LHC) and the International Linear Collider (ILC) promise to improve the experimental precision of key observables used in the fits. This paper presents updated electroweak fit results using the latest NNLO theoretical predictions and prospects for the LHC and ILC. The impact of experimental and theoretical uncertainties is analysed in detail. We compare constraints from the electroweak fit on the Higgs couplings with direct LHC measurements, and we examine present and future prospects of these constraints using a model with modified couplings of the Higgs boson to fermions and bosons.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
In view of the discovery of a new boson by the ATLAS and CMS Collaborations at the LHC, we present an update of the global Standard Model (SM) fit to electroweak precision data. Assuming the new ...particle to be the SM Higgs boson, all fundamental parameters of the SM are known allowing, for the first time, to overconstrain the SM at the electroweak scale and assert its validity. Including the effects of radiative corrections and the experimental and theoretical uncertainties, the global fit exhibits a
p
-value of 0.07. The mass measurements by ATLAS and CMS agree within 1.3
σ
with the indirect determination
. Within the SM the
W
boson mass and the effective weak mixing angle can be accurately predicted to be
M
W
=80.359±0.011 GeV and
from the global fit. These results are compatible with, and exceed in precision, the direct measurements. For the indirect determination of the top quark mass we find
, in agreement with the kinematic and cross-section-based measurements.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present an update of the Standard Model fit to electroweak precision data. We include newest experimental results on the top-quark mass, the
W
mass and width, and the Higgs-boson mass bounds from ...LEP, Tevatron and the LHC. We also include a new determination of the electromagnetic coupling strength at the
Z
pole. We find for the Higgs-boson mass
and
when not including and including the direct Higgs searches, respectively. From the latter fit we indirectly determine the
W
mass to be
. We exploit the data to determine experimental constraints on the oblique vacuum polarisation parameters, and confront these with predictions from the Standard Model (SM) and selected SM extensions. By fitting the oblique parameters to the electroweak data we derive allowed regions in the BSM parameter spaces. We revisit and consistently update these constraints for a fourth fermion generation, two Higgs doublet, inert Higgs and littlest Higgs models, models with large, universal or warped extra dimensions and technicolour. In most of the models studied a heavy Higgs boson can be made compatible with the electroweak precision data.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We present an interpretable implementation of the autoencoding algorithm, used as an anomaly detector, built with a forest of deep decision trees on FPGA, field programmable gate arrays. Scenarios at ...the Large Hadron Collider at CERN are considered, for which the autoencoder is trained using known physical processes of the Standard Model. The design is then deployed in real-time trigger systems for anomaly detection of unknown physical processes, such as the detection of rare exotic decays of the Higgs boson. The inference is made with a latency value of 30 ns at percent-level resource usage using the Xilinx Virtex UltraScale+ VU9P FPGA. Our method offers anomaly detection at low latency values for edge AI users with resource constraints.
A prior Radiation Therapy Oncology Group (RTOG) clinical trial in anaplastic oligodendroglioma suggested a progression-free survival benefit for procarbazine, lomustine, and vincristine (PCV) ...chemotherapy in addition to radiation therapy (RT), as have smaller trials in low-grade glioma (LGG).
Eligibility criteria included supratentorial WHO grade 2 LGG, age 18 to 39 years with subtotal resection/biopsy, or age ≥ 40 years with any extent resection. Patients were randomly assigned to RT alone or RT followed by six cycles of PCV. Survival was compared by using the modified Wilcoxon and log-rank tests.
In all, 251 patients were accrued from 1998 to 2002. Median overall survival (OS) time and 5-year OS rates for RT versus RT + PCV were 7.5 years versus not reached and 63% versus 72%, respectively (hazard ratio HR; 0.72; 95% CI, 0.47 to 1.10; P = .33; log-rank P = .13). Median progression-free survival (PFS) time and 5-year PFS rates for RT versus RT + PCV were 4.4 years versus not reached and 46% versus 63%, respectively (HR, 0.6; 95% CI, 0.41 to 0.86; P = .06; log-rank P = .005). OS and PFS were similar for all patients between years 0 and 2. After 2 years, OS and PFS curves separated significantly, favoring RT + PCV. For 2-year survivors (n = 211), the probability of OS for an additional 5 years was 74% with RT + PCV versus 59% with RT alone (HR, 0.52; 95% CI, 0.30 to 0.90; log-rank P = .02).
PFS but not OS was improved for adult patients with LGG receiving RT + PCV versus RT alone. On post hoc analysis, for 2-year survivors, the addition of PCV to RT conferred a survival advantage, suggesting a delayed benefit for chemotherapy.
Progesterone receptors are expressed in approximately 70% of meningiomas. Mifepristone is an oral antiprogestational agent reported to have modest activity in a phase II study. This multicenter, ...prospective, randomized, placebo-controlled phase III trial conducted by SWOG was planned to define the role of mifepristone in the treatment of unresectable meningioma.
Eligible patients were randomly assigned to receive either mifepristone or placebo for 2 years unless disease progressed. Patients who were stable or responding to protocol therapy after 2 years had the option to continue with the same blinded therapy. Serial follow-up allowed assessment of efficacy and toxicity. Time to treatment failure and overall survival were ascertained for all randomly assigned patients. On progression, patients receiving placebo could cross over and receive active drug.
Among 164 eligible patients, 80 were randomly assigned to mifepristone and 84 to placebo. Twenty-four patients (30%) were able to complete 2 years of mifepristone without disease progression, adverse effects, or other reasons for discontinuation. Twenty-eight patients (33%) in the placebo arm completed the 2-year study. There was no statistical difference between the arms in terms of failure-free or overall survival.
Long-term administration of mifepristone was well tolerated but had no impact on patients with unresectable meningioma.
Central place foragers, such as pollinating bees, typically develop circuits (traplines) to visit multiple foraging sites in a manner that minimizes overall travel distance. Despite being ...taxonomically widespread, these routing behaviours remain poorly understood due to the difficulty of tracking the foraging history of animals in the wild. Here we examine how bumblebees (Bombus terrestris) develop and optimise traplines over large spatial scales by setting up an array of five artificial flowers arranged in a regular pentagon (50 m side length) and fitted with motion-sensitive video cameras to determine the sequence of visitation. Stable traplines that linked together all the flowers in an optimal sequence were typically established after a bee made 26 foraging bouts, during which time only about 20 of the 120 possible routes were tried. Radar tracking of selected flights revealed a dramatic decrease by 80% (ca. 1500 m) of the total travel distance between the first and the last foraging bout. When a flower was removed and replaced by a more distant one, bees engaged in localised search flights, a strategy that can facilitate the discovery of a new flower and its integration into a novel optimal trapline. Based on these observations, we developed and tested an iterative improvement heuristic to capture how bees could learn and refine their routes each time a shorter route is found. Our findings suggest that complex dynamic routing problems can be solved by small-brained animals using simple learning heuristics, without the need for a cognitive map.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
With the high costs of operating room time, minimizing potential causes of time waste is financially beneficial to surgeons and hospitals. The time needed to activate a chlorhexidine gluconate ...surgical solution applicator presents an opportunity for optimization. Many techniques are employed to expedite the process, but there have been no studies comparing these techniques.
To determine the most efficient method for utilizing a chlorhexidine gluconate surgical prep applicator.
Six techniques were tested to determine which caused the sponge of a Chloraprep™ applicator to become saturated quickest. These were a single squeeze (control), up-and-down shaking, side-to-side shaking, pressing the sponge on a surface (dab), pressing with cotton swabs (poke), and continuously squeezing the lever of the applicator. The time between the internal glass breaking in the applicator to the time of sponge saturation with solution was measured for each technique. Times were then compared to determine which technique best expedited the process.
The side-to-side shake, up-and-down shake, and ‘dab’ techniques were each significantly faster than the control group. Side-to-side shaking had the fastest time to sponge saturation on average. The average difference in time to saturation between the side-to-side shake technique and the ‘poke’ technique may be as much as 27.5 s.
Utilization of the side-to-side shake technique, as well as the up-and-down shake and ‘dab’ techniques, significantly expedite the time it takes to use a chlorhexidine gluconate applicator. The time savings from employing these techniques could result in significant financial benefits.
The global fit of the Standard Model to electroweak precision data, routinely performed by the LEP electroweak working group and others, demonstrated impressively the predictive power of electroweak ...unification and quantum loop corrections. We have revisited this fit in view of (i) the development of the new generic fitting package,
Gfitter
, allowing for flexible and efficient model testing in high-energy physics, (ii) the insertion of constraints from direct Higgs searches at LEP and the Tevatron, and (iii) a more thorough statistical interpretation of the results. Gfitter is a modular fitting toolkit, which features predictive theoretical models as independent plug-ins, and a statistical analysis of the fit results using toy Monte Carlo techniques. The state-of-the-art electroweak Standard Model is fully implemented, as well as generic extensions to it. Theoretical uncertainties are explicitly included in the fit through scale parameters varying within given error ranges.
This paper introduces the Gfitter project, and presents state-of-the-art results for the global electroweak fit in the Standard Model (SM), and for a model with an extended Higgs sector (2HDM). Numerical and graphical results for fits with and without including the constraints from the direct Higgs searches at LEP and Tevatron are given. Perspectives for future colliders are analysed and discussed.
In the SM fit including the direct Higgs searches, we find
M
H
=116.4
−1.3
+18.3
GeV, and the 2
σ
and 3
σ
allowed regions 114,145 GeV and 113,168 and 180,225 GeV, respectively. For the strong coupling strength at fourth perturbative order we obtain
α
S
(
M
Z
2
)=0.1193
−0.0027
+0.0028
(exp )±0.0001 (theo). Finally, for the mass of the top quark, excluding the direct measurements, we find
m
t
=178.2
−4.2
+9.8
GeV. In the 2HDM we exclude a charged-Higgs mass below 240 GeV at 95% confidence level. This limit increases towards larger tan
β
, e.g.,
is excluded for tan
β
=70.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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