399 research outputs found
Towards two-loop automation in OpenLoops
NLO scattering amplitudes are provided by fully automated numerical tools,
such as OpenLoops, for a very wide range of processes. In order to match the
numerical precision of current and future collider experiments, the higher
precision of NNLO calculations is essential, and their automation in a similar
tool a highly desirable goal. In our approach, D-dimensional two-loop
amplitudes are decomposed into Feynman integrals with four-dimensional
numerators and (D-4)-dimensional remainders. The latter are reconstructed
through process-independent rational counterterm insertions into lower-loop
diagrams, while the first are expressed as loop momentum tensor integrals
contracted with tensor coefficients. In this article, we describe a completely
generic algorithm, first presented in [1], for the efficient and numerically
stable construction of these tensor coefficients. This algorithm is fully
implemented in the OpenLoops framework for QED and QCD corrections to the
Standard Model. For this implementation we present performance studies on
numerical stability and CPU efficiency.Comment: Contribution to the proceedings of "Loops and Legs in Quantum Field
Theory - LL2022", 25-30 April, 2022, Ettal, German
Are spectroscopic factors from transfer reactions consistent with asymptotic normalisation coefficients?
It is extremely important to devise a reliable method to extract
spectroscopic factors from transfer cross sections. We analyse the standard
DWBA procedure and combine it with the asymptotic normalisation coefficient,
extracted from an independent data set. We find that the single particle
parameters used in the past generate inconsistent asymptotic normalization
coefficients. In order to obtain a consistent spectroscopic factor,
non-standard parameters for the single particle overlap functions can be used
but, as a consequence, often reduced spectroscopic strengths emerge. Different
choices of optical potentials and higher order effects in the reaction model
are also studied. Our test cases consist of: C(d,p)C(g.s.) at
MeV, O(d,p)O(g.s.) at MeV and
Ca(d,p)Ca(g.s.) at MeV. We underline the
importance of performing experiments specifically designed to extract ANCs for
these systems.Comment: 15 pages, 12 figures, Phys. Rev. C (in press
Disseminated Fusarium oxysporum Infection in Hemophagocytic Lymphohistiocytosis
Abstract : The portal of entry of disseminated Fusarium spp. infections is still not clearly defined. We report on a disseminated Fusarium oxysporum infection occurring during a long period of severe neutropenia in a child with hemophagocytic lymphohistiocytosis. A nasogastric feeding tube was the possible source of entry of the fungu
NO x reduction in the exhaust of mobile heavy-duty diesel engines by urea-SCR
A DeNO x demonstration system for a diesel engine used in construction machineries and mobile cranes was setup. In preliminary experiments various extruded and coated SCR catalysts were evaluated with and without oxidizing pre-catalyst. The data from stationary tests with two selected catalysts were used to establish various model-based control algorithms for the optimum dosage of urea in the ESC and ETC. A NO x conversion of >93% at <10ppm average ammonia slip could be achieved at a converter-to-swept volume ratio of <2.
Pooling as a strategy for the timely diagnosis of soil-transmitted helminths in stool: value and reproducibility
Background
The strategy of pooling stool specimens has been extensively used in the field of parasitology in order to facilitate the screening of large numbers of samples whilst minimizing the prohibitive cost of single sample analysis. The aim of this study was to develop a standardized reproducible pooling protocol for stool samples, validated between two different laboratories, without jeopardizing the sensitivity of the quantitative polymerase chain reaction (qPCR) assays employed for the detection of soil-transmitted helminths (STHs). Two distinct experimental phases were recruited. First, the sensitivity and specificity of the established protocol was assessed by real-time PCR for each one of the STHs. Secondly, agreement and reproducibility of the protocol between the two different laboratories were tested. The need for multiple stool sampling to avoid false negative results was also assessed. Finally, a cost exercise was conducted which included labour cost in low- and high-wage settings, consumable cost, prevalence of a single STH species, and a simple distribution pattern of the positive samples in pools to estimate time and money savings suggested by the strategy.
Results
The sensitivity of the pooling method was variable among the STH species but consistent between the two laboratories. Estimates of specificity indicate a âpooling approachâ can yield a low frequency of âmissedâ infections. There were no significant differences regarding the execution of the protocol and the subsequent STH detection between the two laboratories, which suggests in most cases the protocol is reproducible by adequately trained staff. Finally, given the high degree of agreement, there appears to be little or no need for multiple sampling of either individuals or pools.
Conclusions
Our results suggest that the pooling protocol developed herein is a robust and efficient strategy for the detection of STHs in âpools-of-fiveâ. There is notable complexity of the pool preparation to ensure even distribution of helminth DNA throughout. Therefore, at a given setting, cost of labour among other logistical and epidemiological factors, is the more concerning and determining factor when choosing pooling strategies, rather than losing sensitivity and/or specificity of the molecular assay or the method.Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated
DEVELOPMENT AND VALIDATION OF A PET RADIOMICSÂ PROGNOSTIC MODEL FOR DIFFUSE LARGE B CELLÂ LYMPHOMA
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Wake response to an ocean-feedback mechanism: Madeira Island case study
This discussion focused on the numerical study of a wake episode. The Weather
Research and Forecasting model was used in a downscale mode. The current
literature focuses the discussion on the adiabatic dynamics of atmospheric
wakes. Changes in mountain height and consequently on its relation to the
atmospheric inversion layer should explain the shift in wake regimes: from a
'strong-wake' to a 'weak-wake' scenario. Nevertheless, changes in SST
variability can also induce similar regime shifts. Increase in evaporation,
contributes to increase convection and thus to an uplift of the stratified
atmospheric layer, above the critical height, with subsequent internal gravity
wave activity.Comment: Under review proces
Guilt is effectively induced by a written auto-biographical essay but not reduced by experimental pain.
Introduction
The aim of the present study was (1) to validate the method of guilt-induction by means of a written auto-biographical essay and (2) to test whether experimental pain is apt to alleviate the mental burden of guilt, a concept receiving support from both empirical research and clinical observation.
Methods
Three independent groups of healthy male participants were recruited. Group allocation was not randomized but within group pain/sham administration was counterbalanced over the two test-days. Groups were tested in the following consecutive order: Group A: guilt induction, heat-pain/sham, N = 59; Group B: guilt induction, cold-pressure-pain/sham, N = 43; Group C: emotionally neutral induction, heat-pain/sham, N = 39. Guilt was induced on both test-days in group A and B before pain/sham administration. Visual analog scale (VAS) guilt ratings immediately after pain/sham stimulation served as the primary outcome. In a control group C the identical heat-pain experiment was performed like in group A but a neutral emotional state was induced.
Results
A consistently strong overall effect of guilt-induction (heat-pain: p < 0.001, effect size r = 0.71; CPT-pain p < 0.001, r = 0.67) was found when compared to the control-condition (p = 0.25, r = 0.08). As expected, heat- and cold-pressure-stimuli were highly painful in all groups (p < 0.0001, r = 0.89). However, previous research supporting the hypothesis that pain is apt to reduce guilt was not replicated.
Conclusion
Although guilt-induction was highly effective on both test-days no impact of pain on behavioral guilt-ratings in healthy individuals could be identified. Guilt induction per se did not depend on the order of testing. The result questions previous experimental work on the impact of pain on moral emotions
Strongyloides stercoralis larvae excretion patterns before and after treatment
The variability of larval excretion impedes the parasitological diagnosis of Strongyloides stercoralis in infected individuals. We assessed the number of larvae excreted per gram (LPG) stool in 219 samples from 38 infected individuals over 7 consecutive days before and in 470 samples from 44 persons for 21 consecutive days after ivermectin treatment (200ÎŒgkgâ1 BW). The diagnostic sensitivity of a single stool sample was about 75% for individuals with low-intensity infections (â©œ1 LPG) and increased to 95% for those with high-intensity infections (â©Ÿ10 LPG). Doubling the number of samples examined per person increased sensitivity to more than 95%, even for low-intensity infections. There was no indication of a cyclic excretion of larvae. After treatment, all individuals stopped excreting larvae within 3 days. Larvae were not detected during any of the following 18 days (total 388 Baermann and 388 Koga Agar tests). Two stool samples, collected on consecutive days, are recommended in settings where low or heterogeneous infection intensities are likely. In this way, taking into account the possible biological variability in excretion, the efficacy of ivermectin treatment can be assessed as soon as 4 days after treatmen
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