Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Input-specific control of reward and aversion in the ventral tegmental area

Ventral tegmental area (VTA) dopamine neurons have important roles in adaptive and pathological brain functions related to reward and motivation. However, it is unknown whether subpopulations of VTA dopamine neurons participate in distinct circuits that encode different motivational signatures, and whether inputs to the VTA differentially modulate such circuits. Here we show that, because of differences in synaptic connectivity, activation of inputs to the VTA from the laterodorsal tegmentum and the lateral habenula elicit reward and aversion in mice, respectively. Laterodorsal tegmentum neurons preferentially synapse on dopamine neurons projecting to the nucleus accumbens lateral shell, whereas lateral habenula neurons synapse primarily on dopamine neurons projecting to the medial prefrontal cortex as well as on GABAergic (γ-aminobutyric-acid-containing) neurons in the rostromedial tegmental nucleus. These results establish that distinct VTA circuits generate reward and aversion, and thereby provide a new framework for understanding the circuit basis of adaptive and pathological motivated behaviours.National Institutes of Health (U.S.) (Grant NIH NS069375)JPB FoundationNational Institute of Mental Health (U.S.

Cost-Effectiveness of Alternative Anticoagulation Strategies for Postoperative Management of Total Knee Arthroplasty Patients

Background: Anticoagulation is essential for deep vein thrombosis (DVT) and pulmonary embolism (PE) prevention following total knee arthroplasty (TKA). Some research has suggested that longer duration anticoagulation can substantially reduce the risks of DVT and PE; however, in the absence of definitive recommendations, physicians are left weighing the risks of DVT and PE against those of anticoagulation, including gastrointestinal (GI) and central nervous system (CNS) hemorrhage and increased likelihood of prosthetic joint infection (PJI). We conducted a cost-effectiveness analysis to evaluate the benefits and risks of 14- and 35-day therapy with the most commonly prescribed anticoagulants post-TKA. Background: Anticoagulation is essential for deep vein thrombosis (DVT) and pulmonary embolism (PE) prevention following total knee arthroplasty (TKA). Some research has suggested that longer duration anticoagulation can substantially reduce the risks of DVT and PE; however, in the absence of definitive recommendations, physicians are left weighing the risks of DVT and PE against those of anticoagulation, including gastrointestinal (GI) and central nervous system (CNS) hemorrhage and increased likelihood of prosthetic joint infection (PJI). We conducted a cost-effectiveness analysis to evaluate the benefits and risks of 14- and 35-day therapy with the most commonly prescribed anticoagulants post-TKA. Results: Aspirin resulted in the highest cumulative incidence of DVT and PE, while prolonged fondaparinux led to the largest reduction in DVT incidence (15% reduction compared to no prophylaxis). Despite differential bleeding rates (ranging from 3% to 6%), all strategies had similar incidence of PJI (1-2%). Prolonged rivaroxaban was the least costly strategy ($3,300 one year post-TKA) and the preferred regimen in the base case. In sensitivity analyses, prolonged rivaroxaban and prolonged warfarin had similar likelihoods of being cost-effective. Conclusions: For all anticoagulants, extending the duration of anticoagulation therapy in the post-operative period to 35 days increases QALYs compared to standard 14-day prophylaxis. Prolonged rivaroxaban and prolonged warfarin are most likely to be cost-effective in TKA patients; the costs of fondaparinux and LMWH precluded their being preferred strategies. As warfarin and rivaroxaban are comparable from a cost-effectiveness standpoint, patient preferences can help inform the appropriate post-TKA prophylaxis

A Phase I study of the safety, pharmacokinetics and efficacy of navitoclax plus docetaxel in patients with advanced solid tumors

Aim: This Phase I study investigated safety of navitoclax and docetaxel in patients (n = 41) with advanced solid tumors. Patients & methods: Two navitoclax plus docetaxel dosing schedules (21 and 28 days) were evaluated. Maximum tolerated dose, dose-limiting toxicities and preliminary antitumor activity were assessed. Results: Ten (24%) patients experienced dose-limiting toxicities; dose-escalation cohorts: n = 7 (21-day schedule: n = 5; 28-day schedule: n = 2) and 21-day expanded safety cohort: n = 3. Navitoclax 150-mg days 1-5 every 21 days with docetaxel 75 mg/m2 day 1 was the maximum tolerated dose and optimal schedule. Adverse events included thrombocytopenia (63%), fatigue (61%), nausea (59%) and neutropenia (51%). Four confirmed partial responses occurred. Conclusion: Navitoclax 150-mg orally once/day was safely administered with docetaxel. Myelosuppression limited dose escalation; antitumor activity was observed. Clinical trial registration: NCT00888108 (ClinicalTrials.gov)

Measurements of integrated and differential cross sections for isolated photon pair production in pp collisions at √s=8 TeV with the ATLAS detector

A measurement of the production cross section for two isolated photons in proton-proton collisions at a center-of-mass energy of √s=8 TeV is presented. The results are based on an integrated luminosity of 20.2 fb−1 recorded by the ATLAS detector at the Large Hadron Collider. The measurement considers photons with pseudorapidities satisfying |ηγ|40GeV and EγT,2>30 GeV for the two leading photons ordered in transverse energy produced in the interaction. The background due to hadronic jets and electrons is subtracted using data-driven techniques. The fiducial cross sections are corrected for detector effects and measured differentially as a function of six kinematic observables. The measured cross section integrated within the fiducial volume is 16.8 ± 0.8  pb . The data are compared to fixed-order QCD calculations at next-to-leading-order and next-to-next-to-leading-order accuracy as well as next-to-leading-order computations including resummation of initial-state gluon radiation at next-to-next-to-leading logarithm or matched to a parton shower, with relative uncertainties varying from 5% to 20%

Search for the direct production of charginos and neutralinos in final states with tau leptons in √s=13 TeV collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with at least two hadronically decaying tau leptons is presented. The analysis uses a dataset of pp collisions corresponding to an integrated luminosity of 36.1 fb−1, recorded with the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13TeV.Nosignificant deviation from the expected Standard Model background is observed. Limits are derived in scenarios of ˜χ+1 ˜χ−1 pair production and of ˜χ±1 ˜χ02 and ˜χ+1 ˜χ−1 production in simplified models where the neutralinos and charginos decay solely via intermediate left-handed staus and tau sneutrinos, and the mass of the ˜ τL state is set to be halfway between the masses of the ˜χ±1 and the ˜χ01. Chargino masses up to 630 GeV are excluded at 95% confidence level in the scenario of direct production of ˜χ+1 ˜χ−1 for a massless ˜χ01. Common ˜χ±1 and ˜χ02 masses up to 760 GeV are excluded in the case of production of ˜χ±1 ˜χ02 and ˜χ+1 ˜χ−1 assuming a massless ˜χ01. Exclusion limits for additional benchmark scenarios with large and small mass-splitting between the ˜χ±1 and the ˜χ01 are also studied by varying the ˜ τL mass between the masses of the ˜χ±1 and the ˜χ01

QCD and strongly coupled gauge theories : challenges and perspectives

We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe

Measurement of the cross section for inclusive isolated-photon production in pp collisions at √s=13TeV using the ATLAS detector

Inclusive isolated-photon production in pp collisions at a centre-of-mass energy of 13TeVis studied with the ATLAS detector at the LHC using a data set with an integrated luminosity of 3.2fb−1. The cross section is measured as a function of the photon transverse energy above 125GeVin different regions of photon pseudorapidity. Next-to-leading-order perturbative QCD and Monte Carlo event-generator predictions are compared to the cross-section measurements and provide an adequate description of the data

Search for dark matter at √s=13 TeV in final states containing an energetic photon and large missing transverse momentum with the ATLAS detector

Results of a search for physics beyond the Standard Model in events containing an energetic photon and large missing transverse momentum with the ATLAS detector at the Large Hadron Collider are reported. As the number of events observed in data, corresponding to an integrated luminosity of 36.1 fb−1 of proton–proton collisions at a centre-of-mass energy of 13 TeV, is in agreement with the Standard Model expectations, model-independent limits are set on the fiducial cross section for the production of events in this final state. Exclusion limits are also placed in models where dark-matter candidates are pair-produced. For dark-matter production via an axial-vector or a vector mediator in the s-channel, this search excludes mediator masses below 750–1200 GeV for dark-matter candidate masses below 230–480 GeV at 95% confidence level, depending on the couplings. In an effective theory of dark-matter production, the limits restrict the value of the suppression scale M∗ to be above 790 GeV at 95% confidence level. A limit is also reported on the production of a high-mass scalar resonance by processes beyond the Standard Model, in which the resonance decays to Zγ and the Z boson subsequently decays into neutrinos

Studies of Zγ production in association with a high-mass dijet system in pp collisions at √s=8 TeV with the ATLAS detector

The production of a Z boson and a photon in association with a high-mass dijet system is studied using 20.2 fb −1 of proton-proton collision data at a centre-of-mass energy of s=8 TeV recorded with the ATLAS detector in 2012 at the Large Hadron Collider. Final states with a photon and a Z boson decaying into a pair of either electrons, muons, or neutrinos are analysed. Electroweak and total pp → Zγjj cross-sections are extracted in two fiducial regions with different sensitivities to electroweak production processes. Quartic couplings of vector bosons are studied in regions of phase space with an enhanced contribution from pure electroweak production, sensitive to vector-boson scattering processes VV → Zγ. No deviations from Standard Model predictions are observed and constraints are placed on anomalous couplings parameterized by higher-dimensional operators using effective field theory.[Figure not available: see fulltext.]