For the investigation of higher order Feynman integrals, potentially with tensor structure, it is highly desirable to have numerical methods and automated tools for dedicated, but sufficiently ...‘simple’ numerical approaches. We elaborate two algorithms for this purpose which may be applied in the Euclidean kinematical region and in
d
=4−2
ε
dimensions. One method uses Mellin–Barnes representations for the Feynman parameter representation of multi-loop Feynman integrals with arbitrary tensor rank. Our Mathematica package AMBRE has been extended for that purpose, and together with the packages MB (M. Czakon) or MBresolve (A.V. Smirnov and V.A. Smirnov) one may perform automatically a numerical evaluation of planar tensor Feynman integrals. Alternatively, one may apply sector decomposition to planar and non-planar multi-loop
ε
-expanded Feynman integrals with arbitrary tensor rank. We automatized the preparations of Feynman integrals for an immediate application of the package sector_decomposition (C. Bogner and S. Weinzierl) so that one has to give only a proper definition of propagators and numerators. The efficiency of the two implementations, based on Mellin–Barnes representations and sector decompositions, is compared. The computational packages are publicly available.
We discuss theoretical predictions for the production of five hard jets at next-to-leading order accuracy QCD at the Large Hadron Collider. Results are shown for both the total cross section as well ...as for differential distributions of the jet transverse momenta and rapidities. As a general pattern, we find moderate corrections of the order of 10% with respect to the LO result and a significant reduction of the scale dependence. Furthermore, ratios of different jet-multiplicity are studied. Our results are compared with data from the ATLAS collaboration.
We present the computation of the NLO QCD corrections to the production of a Standard Model Higgs boson in association with up to three jets through gluon-gluon fusion. The computation is performed ...in the approximation of an infinitely heavy top quark. Before studying some phenomenologically important observables, we describe some technical detail about the computation.
In these proceedings we report our progress in the development of the publicly available C++ library NJet for accurate calculations of high-multiplicity one-loop amplitudes. As a phenomenological ...application we present the first complete next-to-leading order (NLO) calculation of five jet cross section at hadron colliders.
Background
. Epidural spinal cord compression (ESCC) is the most common neurological complication in metastatic spinal tumours.
Materials and methods
. The study included 87 spinal malignancy ...patients operated within 01.01.2014–30.09.2021. All patients had a type of palliative decompressive and stabilising surgery: standard posterior access (SPA, 55 patients), minimally invasive posterior access (MPA, 22 patients) or anterior access (AA, 10 patients).
Results
. The patient cohorts did not differ significantly by the duration of surgery, length of hospital stay, rates and types of postoperative complications. The AA cohort revealed a statistical difference by intraoperative blood loss. A Karnofsky performance status was statistically improved post- vs. pre-surgery (p < 0.05) at no significant change of Frankel neurological function status (p > 0.05). A Kaplan — Meier curve analysis showed no significant survival rate variation among the surgical techniques. Discussion. Our results suggest that posterior access interventions should be considered optimal. We report no statistical difference in the postoperative neurological and performance status dynamics between both cohorts, which encourages the MPA use in all patients with minimal epidural compression.
Conclusion
. Posterior access with cytoreductive tumour removal in anterior spinal cord compression is advantageous over anterior surgery. A posterior access surgery with minimal spinal canal decompression is recommended in all patients with grade 1 tumoural epidural compression.
Objective:
Improvement of the results of treatment of vertebral tumors with neural compression by means of analyzing the authors’ experience.
Material and methods:
The study included 151 patients ...with primary and metastatic vertebral tumors, operated in the neurosurgical departments of three large medical institutions from 01.01.2014 to 31.12.2020.
Results:
Most of the patients underwent palliative interventions. Radical surgery (marginal or wide resection of the tumor) was performed in 8 (5%) patients. Surgical treatment as the only method of treatment was used in 75 (50%) cases, combined treatment was used in 42 (28%) people, complex treatment – in 34 (22%). The immediate results of treatment of 91% of patients were characterized by the absence of negative dynamics in the neurological status and in 50% of cases by positive dynamics in the functional state. Among patients with malignant tumors and a traced catamnesis, the one-year survival rate was 66%, three-year – 52%, five-year – 47%. The median overall survival rate was 12.8 months, the median event-free survival rate was 12.55 months.
Conclusion:
The use of non-radical interventions in the surgery of vertebral tumors with neural compression expands the possibilities of minimizing surgical trauma, while maintaining the neurological and improving the functional status of the patient.
A
bstract
KLOE and Babar have an observed discrepancy of 2% to 5% in the invariant pion pair production cross section. These measurements are based on approximate NLO
μ
+
μ
−
γ
cross section ...predictions of the Monte Carlo event generator PHOKHARA7.0. In this article, the complete NLO radiative corrections to
μ
+
μ
−
γ
production are calculated and implemented in the Monte Carlo event generator PHOKHARA9.0. Numerical reliability is guaranteed by two independent approaches to the real and the virtual corrections. The novel features include the contribution of pentagon diagrams in the virtual corrections, which form a gauge-invariant set when combined with their box diagram partners. They may contribute to certain distributions at the percent level. Also the real emission was complemented with two-photon final state emission contributions not included in the generator PHOKHARA7.0. We demonstrate that the numerical influence reaches, for realistic charge-averaged experimental setups, not more than 0.1% at KLOE and 0.3% at BaBar energies. As a result, we exclude the approximations in earlier versions of PHOKHARA as origin of the observed experimental discrepancy.
We present an update of the Binoth Les Houches Accord (BLHA) to standardise the interface between Monte Carlo programs and codes providing one-loop matrix elements.
Measurements of Pollution in the Troposphere (MOPITT) is a new remote sensing instrument aboard the Earth Observing System (EOS) “Terra” satellite which exploits gas correlation radiometry principles ...to quantify tropospheric concentrations of carbon monoxide (CO) and methane (CH4). The MOPITT CO retrieval algorithm employs a nonlinear optimal estimation method to iteratively solve for the CO profile which is statistically most consistent with both the satellite‐measured radiances and a priori information. The algorithm's theoretical basis is described in terms of the observed radiances and their weighting functions, the a priori information, and the retrieval averaging kernels. Examples of actual CO retrievals over scenes with contrasting pollution conditions are demonstrated, and interpreted in the context of the retrieval averaging kernels and a priori.
KLOE and Babar have an observed discrepancy of 2% to 5% in the invariant pion pair production cross section. These measurements are based on approximate NLO mu super(+) mu super(-) gamma cross ...section predictions of the Monte Carlo event generator PHOKHARA7.0. In this article, the complete NLO radiative corrections to mu super(+) mu super(-) gamma production are calculated and implemented in the Monte Carlo event generator PHOKHARA9.0. Numerical reliability is guaranteed by two independent approaches to the real and the virtual corrections. The novel features include the contribution of pentagon diagrams in the virtual corrections, which form a gauge-invariant set when combined with their box diagram partners. They may contribute to certain distributions at the percent level. Also the real emission was complemented with two-photon final state emission contributions not included in the generator PHOKHARA7.0. We demonstrate that the numerical influence reaches, for realistic charge-averaged experimental setups, not more than 0.1% at KLOE and 0.3% at BaBar energies. As a result, we exclude the approximations in earlier versions of PHOKHARA as origin of the observed experimental discrepancy.
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