A
bstract
We present results from a state-of-the-art fit of electroweak precision observables and Higgs-boson signal-strength measurements performed using 7 and 8 TeV data from the Large Hadron ...Collider. Based on the HEPfit package, our study updates the traditional fit of electroweak precision observables and extends it to include Higgs-boson measurements. As a result we obtain constraints on new physics corrections to both electroweak observables and Higgs-boson couplings. We present the projected accuracy of the fit taking into account the expected sensitivities at future colliders.
We assess the impact of the very recent measurement of the top-quark mass by the CMS Collaboration on the fit of electroweak data in the standard model and beyond, with particular emphasis on the ...prediction for the mass of the W boson. We then compare this prediction with the average of the corresponding experimental measurements including the new measurement by the CDF Collaboration, and discuss its compatibility in the standard model, in new physics models with oblique corrections, and in the dimension-six standard model effective field theory. Finally, we present the updated global fit to electroweak precision data in these models.
HEPfit is a flexible open-source tool which, given the Standard Model or any of its extensions, allows to (i) fit the model parameters to a given set of experimental observables; (ii) obtain ...predictions for observables. HEPfit can be used either in Monte Carlo mode, to perform a Bayesian Markov Chain Monte Carlo analysis of a given model, or as a library, to obtain predictions of observables for a given point in the parameter space of the model, allowing HEPfit to be used in any statistical framework. In the present version, around a thousand observables have been implemented in the Standard Model and in several new physics scenarios. In this paper, we describe the general structure of the code as well as models and observables implemented in the current release.
We present results from the analytic calculation of ttH hadronic production at next-to-leading order in QCD interfaced with parton-shower Monte Carlo event generators in the POWHEG BOX framework. We ...consider kinematic distributions of the top quark and Higgs boson at the 8 TeV Large Hadron Collider and study the theoretical uncertainties due to specific choices of renormalization/factorization scales and parton-showering algorithms, namely PYTHIA and HERWIG. The importance of spin correlations in the production and decay stages of a top/antitop quark is discussed on the example of kinematic distributions of leptons originating from the top/antitop decays. The corresponding code is now part of the public release of the POWHEG BOX.
We present a new Monte Carlo event generator for the production of a top-quark pair in association with a W± boson at hadron colliders in the POWHEG-BOX framework. We consider the ...next-to-leading-order QCD corrections to the pp → t¯t W± cross section, corresponding to the O(α3sα) and O(αsα3) terms in the perturbative expansion of the parton-level cross section, and model the decays of W and top quarks at leading order retaining spin correlations. The fixed-order QCD calculation is further interfaced with the pythia8 parton-shower event generator via the POWHEG method as implemented in the POWHEG-BOX. The corresponding code is now part of the public repository of the POWHEG-BOX. We perform a comparison of different event generators for both the case of inclusive production and the case of the two same-sign leptons signature at the Large Hadron Collider operating at a center-of-mass energy of 13 TeV. We investigate theoretical uncertainties in the modeling of the fiducial volume stemming from missing higher-order corrections, the different parton-shower-matching schemes, and the modeling of decays. We find that the subleading contribution at O(αsα3) is particularly sensitive to differences in the matching scheme and higher-order parton-shower effects. We observe that in particular jet observables can differ quite visibly although these differences play only a subordinate role in the description of physical observables once all contributions are combined.
The main objective of this work is to study the hydration and properties of calcium sulfoaluminate cement pastes blended with fly ash (FA) and the corresponding mortars at different hydration ages. ...Laboratory X-ray powder diffraction, rheological studies, thermal analysis, porosimetry and compressive strength measurements were performed. The analysis of the diffraction data by Rietveld method allowed quantifying crystalline phases and overall amorphous contents. The studied parameters were: i) FA content, 0, 15 and 30wt.%; and ii) water addition, water-to-CSA mass ratio (w/CSA=0.50 and 0.65), and water-to-binder mass ratio (w/b=0.50). Finally, compressive strengths after 6months of 0 and 15wt.% FA w/CSA=0.50 mortars were similar: 73±2 and 72±3MPa, respectively. This is justified by the filler effect of the FA as no strong evidences of reactivity of FA with CSA were observed. These results support the partial substitution of CSA cements with FA with the economic and environmental benefits.
Yeelimite-containing cements are attracting attention for their tailored properties. Calcium sulfoaluminate, CSA, cements have high contents of Yeelimite and they are used for special applications. ...Belite calcium sulfoaluminate, BCSA or sulfobelite, cements have high contents of belite and intermediate contents of Yeelimite, and they may become an alternative to OPC. Here, we report Rietveld quantitative phase analyses for three commercially available CSA clinkers, one CSA cement, and two laboratory-prepared iron-rich BCSA clinkers. The crystalline phases are reported and quantified. Selective dissolutions are employed for BCSA clinkers to firmly establish their phases. Finally, the overall unaccounted contents (amorphous plus crystalline not quantified) have been determined by two approaches: i) external standard procedure (G-method) with reflection data; ii) internal standard procedure (spiking method with ZnO) with transmission data. The overall unaccounted contents for CSA clinkers were ~10wt.%. Conversely, the unaccounted contents for BCSA clinkers were higher, ~25wt.%.
Context:
Desmopressin is a synthetic agonist of vasopressin receptors (AVPRs). The desmopressin stimulation test is used in the diagnosis and postsurgery prognosis of Cushing disease (CD). However, ...the cellular and molecular mechanisms underlying the desmopressin-induced ACTH increase in patients with CD are poorly understood.
Objective:
The objectives of this study were to determine, for the first time, whether desmopressin acts directly and exclusively on pituitary corticotropinoma cells to stimulate ACTH expression/release and to elucidate the cellular and molecular mechanisms involved in desmopressin-induced ACTH increase in CD.
Design:
A total of 8 normal pituitaries (NPs), 23 corticotropinomas, 14 nonfunctioning pituitary adenomas, 17 somatotropinomas, and 3 prolactinomas were analyzed for AVPR expression by quantitative real-time RT-PCR. Primary cultures derived from corticotropinomas, nonfunctioning pituitary adenomas, somatotropinomas, prolactinomas, and NPs were treated with desmopressin, and ACTH secretion/expression, Ca2+i kinetics, and AVPR expression and/or proliferative response were evaluated. The relationship between AVPR expression and plasma adrenocorticotropin/cortisol levels obtained from desmopressin tests was assessed.
Results:
Desmopressin affects all functional parameters evaluated in corticotropinoma cells but not in NPs or other pituitary adenomas cells. These effects might be due to the dramatic elevation of AVPR1b expression levels found in corticotropinomas. In line with this notion, the use of an AVPR1b antagonist completely blocked desmopressin stimulatory effects. Remarkably, only AVPR1b expression was positively correlated with elevated plasma adrenocorticotropin levels in corticotropinomas.
Conclusions:
The present results provide a cellular and molecular basis to support the desmopressin stimulation test as a reliable, specific test for the diagnosis and postsurgery prognosis of CD. Furthermore, our data indicate that AVPR1b is responsible for the direct/exclusive desmopressin stimulatory pituitary effects observed in CD, thus opening the possibility of exploring AVPR1b antagonists as potential therapeutic tools for CD treatment.
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