34 research outputs found
A comparative study of Higgs boson production from vector-boson fusion
The data taken in Run II at the Large Hadron Collider have started to probe Higgs boson production at high transverse momentum. Future data will provide a large sample of events with boosted Higgs boson topologies, allowing for a detailed understanding of electroweak Higgs boson plus two-jet production, and in particular the vector-boson fusion mode (VBF). We perform a detailed comparison of precision calculations for Higgs boson production in this channel, with particular emphasis on large Higgs boson transverse momenta, and on the jet radius dependence of the cross section. We study fixed-order predictions at next-to-leading order and next-to-next-to-leading order QCD, and compare the results to NLO plus parton shower (NLOPS) matched calculations. The impact of the NNLO corrections on the central predictions is mild, with inclusive scale uncertainties of the order of a few percent, which can increase with the imposition of kinematic cuts. We find good agreement between the fixed-order and matched calculations in non-Sudakov regions, and the various NLOPS predictions also agree well in the Sudakov regime. We analyze backgrounds to VBF Higgs boson production stemming from associated production, and from gluon-gluon fusion. At high Higgs boson transverse momenta, the âyjj and/or mjj cuts typically used to enhance the VBF signal over background lead to a reduced efficiency. We examine this effect as a function of the jet radius and using different definitions of the tagging jets. QCD radiative corrections increase for all Higgs production modes with increasing Higgs boson pT, but the proportionately larger increase in the gluon fusion channel results in a decrease of the gluon-gluon fusion background to electroweak Higgs plus two jet production upon requiring exclusive two-jet topologies. We study this effect in detail and contrast in particular a central jet veto with a global jet multiplicity requirement
Hematologic malignancies following immune checkpoint inhibition for solid tumors
Immune checkpoint inhibition (ICI) can induce durable responses in patients with advanced malignancies. Three cases of hematological neoplasia following ICI for solid tumors have been reported to date. We present five patients treated at our tertiary referral center between 2017 and 2021 who developed chronic myeloid leukemia (two patients), acute myeloid leukemia, myelodysplastic syndrome and chronic eosinophilic leukemia during or after anti-PD-1-based treatment. Molecular analyses were performed on pre-ICI samples to identify baseline variants in myeloid genes. We hypothesize that PD-1 blockade might accelerate progression to overt myeloid malignancies and discuss potential underlying mechanisms
Vermoeider dan ooit: stijgend aantal moeheidsklachten verdient de aandacht van artsen.
Ten opzichte van vijftien jaar geleden hebben aanzienlijk meer mensen last van moeheid. Dat geldt voor mannen en vrouwen van alle leeftijden en alle opleidingsniveaus. Net als vijftien jaar geleden worden de meeste moeheidsklachten gerapporteerd door jonge, hoogopgeleide vrouwen, maar mannen lijken een inhaalslag te maken. De achtergrondkenmerken van vermoeide mensen worden hier beschreven en ook het gebruik dat zij maken van de gezondheidszorg. Wij gaan in op de paradox van de behandeling van moeheid die bij ânormaleâ moeiheidsklachten anders is dan bij pathologische moeheid
Precise predictions for V + 2 jet backgrounds in searches for invisible Higgs decays
We present next-to-leading order QCD and electroweak (EW) theory predictions for V + 2 jet production, with V = Z, W±, considering both the QCD and EW production modes and their interference. We focus on phase-space regions where V + 2 jet production is dominated by vector-boson fusion, and where these processes yield the dominant irreducible backgrounds in searches for invisible Higgs boson decays. Predictions at parton level are provided together with detailed prescriptions for their implementation in experimental analyses based on the reweighting of Monte Carlo samples. The key idea is that, exploiting accurate data for W + 2 jet production in combination with a theory-driven extrapolation to the Z + 2 jet process can lead to a determination of the irreducible background at the few-percent level. Particular attention is devoted to the estimate of the residual theoretical uncertainties due to unknown higher-order QCD and EW effects and their correlation between the different V + 2 jet processes, which is key to improve the sensitivity to invisible Higgs decays
Acute toxicity profile of craniospinal irradiation with intensity-modulated radiation therapy in children with medulloblastoma: A prospective analysis
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152450.pdf (publisher's version ) (Open Access)BACKGROUND: To report on the acute toxicity in children with medulloblastoma undergoing intensity-modulated radiation therapy (IMRT) with daily intrafractionally modulated junctions. METHODS: Newly diagnosed patients, aged 3-21, with standard-risk (SR) or high-risk (HR) medulloblastoma were eligible. A dose of 23.4 or 36.0Gy in daily fractions of 1.8Gy was prescribed to the craniospinal axis, followed by a boost to the primary tumor bed (54 or 55.8Gy) and metastases (39.6-55.8Gy), when indicated. Weekly, an intravenous bolus of vincristine was combined for patients with SR medulloblastoma and patients participating in the COG-ACNS-0332 study. Common toxicity criteria (CTC, version 2.0) focusing on skin, alopecia, voice changes, conjunctivitis, anorexia, dysphagia, gastro-intestinal symptoms, headache, fatigue and hematological changes were scored weekly during radiotherapy. RESULTS: From 2010 to 2014, data from 15 consecutive patients (SR, n = 7; HR, n = 8) were collected. Within 72 h from onset of treatment, vomiting (66 %) and headache (46 %) occurred. During week 3 of treatment, a peak incidence in constipation (33 %) and abdominal pain/cramping (40 %) was observed, but only in the subgroup of patients (n = 9) receiving vincristine (constipation: 56 vs 0 %, P = .04; pain/cramping: 67 vs 0 %, P = .03). At week 6, 73 % of the patients developed faint erythema of the cranial skin with dry desquamation (40 %) or moist desquamation confined to the skin folds of the auricle (33 %). No reaction of the skin overlying the spinal target volume was observed. CONCLUSIONS: Headache at onset and gastro-intestinal toxicity, especially in patients receiving weekly vincristine, were the major complaints of patients with medulloblastoma undergoing craniospinal irradiation with IMRT
Cornering light neutralino dark matter at the LHC
We investigate the current status of the light neutralino dark matter scenario within the minimal supersymmetric standard model (MSSM) taking into account latest results from the LHC. A discussion of the relevant constraints, in particular from the dark matter relic abundance, leads us to a manageable simplified model defined by a subset of MSSM parameters. Within this simplified model we reinterpret a recent search for electroweak supersymmetric particle production based on a signature including multi-taus plus missing transverse momentum performed by the ATLAS collaboration. In this way we derive stringent constraints on the light neutralino parameter space. In combination with further experimental information from the LHC, such as dark matter searches in the monojet channel and constraints on invisible Higgs decays, we obtain a lower bound on the lightest neutralino mass of about 24 GeV. This limit is stronger than any current limit set by underground direct dark matter searches or indirect detection experiments. With a mild improvement of the sensitivity of the multi-tau search, light neutralino dark matter can be fully tested up to about 30 GeV. © SISSA 2013.SCOPUS: ar.jinfo:eu-repo/semantics/publishe
NLO QCD+EW predictions for V + jets including off-shell vector-boson decays and multijet merging
We present next-to-leading order (NLO) predictions including QCD and electroweak (EW) corrections for the production and decay of off-shell electroweak vector bosons in association with up to two jets at the 13 TeV LHC. All possible dilepton final states with zero, one or two charged leptons that can arise from off-shell W and Z bosons or photons are considered. All predictions are obtained using the automated implementation of NLO QCD+EW corrections in the OpenLoops matrix-element generator combined with the Munich and Sherpa Monte Carlo frameworks. Electroweak corrections play an especially important role in the context of BSM searches, due to the presence of large EW Sudakov logarithms at the TeV scale. In this kinematic regime, important observables such as the jet transverse momentum or the total transverse energy are strongly sensitive to multijet emissions. As a result, fixed-order NLO QCD+EW predictions are plagued by huge QCD corrections and poor theoretical precision. To remedy this problem we present an approximate method that allows for a simple and reliable implementation of NLO EW corrections in the MePs@Nlo multijet merging framework. Using this general approach we present an inclusive simulation of vector-boson production in association with jets that guarantees NLO QCD+EW accuracy in all phase-space regions involving up to two resolved jets
Higgs boson pair production at NNLO with top quark mass effects
We consider QCD radiative corrections to Higgs boson pair production through gluon fusion in proton collisions. We combine the exact next-to-leading order (NLO) contribution, which features two-loop virtual amplitudes with the full dependence on the top quark mass M t , with the next-to-next-to-leading order (NNLO) corrections computed in the large-M t approximation. The latter are improved with different reweighting techniques in order to account for finite-M t effects beyond NLO. Our reference NNLO result is obtained by combining one-loop double-real corrections with full M t dependence with suitably reweighted real-virtual and double-virtual contributions evaluated in the large-M t approximation. We present predictions for inclusive cross sections in pp collisions at sâ = 13, 14, 27 and 100 TeV and we discuss their uncertainties due to missing M t effects. Our approximated NNLO corrections increase the NLO result by an amount ranging from +12% at sâ=13 TeV to +7% at sâ=100 TeV, and the residual uncertainty of the inclusive cross section from missing M t effects is estimated to be at the few percent level. Our calculation is fully differential in the Higgs boson pair and the associated jet activity: we also present predictions for various differential distributions at sâ=14 and 100 TeV, and discuss the size of the missing M t effects, which can be larger, especially in the tails of certain observables. Our results represent the most advanced perturbative prediction available to date for this process
Acute toxicity profile of craniospinal irradiation with intensity-modulated radiation therapy in children with medulloblastoma: A prospective analysis
BACKGROUND: To report on the acute toxicity in children with medulloblastoma undergoing intensity-modulated radiation therapy (IMRT) with daily intrafractionally modulated junctions. METHODS: Newly diagnosed patients, aged 3-21, with standard-risk (SR) or high-risk (HR) medulloblastoma were eligible. A dose of 23.4 or 36.0Gy in daily fractions of 1.8Gy was prescribed to the craniospinal axis, followed by a boost to the primary tumor bed (54 or 55.8Gy) and metastases (39.6-55.8Gy), when indicated. Weekly, an intravenous bolus of vincristine was combined for patients with SR medulloblastoma and patients participating in the COG-ACNS-0332 study. Common toxicity criteria (CTC, version 2.0) focusing on skin, alopecia, voice changes, conjunctivitis, anorexia, dysphagia, gastro-intestinal symptoms, headache, fatigue and hematological changes were scored weekly during radiotherapy. RESULTS: From 2010 to 2014, data from 15 consecutive patients (SR, n = 7; HR, n = 8) were collected. Within 72 h from onset of treatment, vomiting (66 %) and headache (46 %) occurred. During week 3 of treatment, a peak incidence in constipation (33 %) and abdominal pain/cramping (40 %) was observed, but only in the subgroup of patients (n = 9) receiving vincristine (constipation: 56 vs 0 %, P = .04; pain/cramping: 67 vs 0 %, P = .03). At week 6, 73 % of the patients developed faint erythema of the cranial skin with dry desquamation (40 %) or moist desquamation confined to the skin folds of the auricle (33 %). No reaction of the skin overlying the spinal target volume was observed. CONCLUSIONS: Headache at onset and gastro-intestinal toxicity, especially in patients receiving weekly vincristine, were the major complaints of patients with medulloblastoma undergoing craniospinal irradiation with IMRT