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The version 3.0 of the Delphes fast-simulation is presented. The goal of Delphes is to allow the simulation of a multipurpose detector for phenomenological studies. The simulation includes a track propagation system embedded in a magnetic field, electromagnetic and hadron calorimeters, and a muon identification system. Physics objects that can be used for data analysis are then reconstructed from the simulated detector response. These include tracks and calorimeter deposits and high level objects such as isolated electrons, jets, taus, and missing energy. The new modular approach allows for greater flexibility in the design of the simulation and reconstruction sequence. New features such as the particle-flow reconstruction approach, crucial in the first years of the LHC, and pile-up simulation and mitigation, which is needed for the simulation of the LHC detectors in the near future, have also been implemented. The Delphes framework is not meant to be used for advanced detector studies, for which more accurate tools are needed. Although some aspects of Delphes are hadron collider specific, it is flexible enough to be adapted to the needs of electron-positron collider experiments.

A measurement of the jet mass distribution in hadronic decays of Lorentz-boosted top quarks is presented. The measurement is performed in the lepton + jets channel of top quark pair production ( ) events, where the lepton is an electron or muon. The products of the hadronic top quark decay are reconstructed using a single large-radius jet with transverse momentum greater than 400 . The data were collected with the CMS detector at the LHC in proton-proton collisions and correspond to an integrated luminosity of 138 . The differential production cross section as a function of the jet mass is unfolded to the particle level and is used to extract the top quark mass. The jet mass scale is calibrated using the hadronic W boson decay within the large-radius jet. The uncertainties in the modelling of the final state radiation are reduced by studying angular correlations in the jet substructure. These developments lead to a significant increase in precision, and a top quark mass of .

The production of Z bosons associated with jets is measured in $$\\text {p}\\text {p}$$ pp collisions at $$\\sqrt{s}=13\\,\\text {Te}\\hspace{-.08em}\\text {V} $$ s = 13 Te V with data recorded with the CMS experiment at the LHC corresponding to an integrated luminosity of 36.3 $$\\,\\text {fb}^{-1}$$ fb - 1 . The multiplicity of jets with transverse momentum $$p_{\\textrm{T}} > 30\\,\\text {Ge}\\hspace{-.08em}\\text {V} $$ p T > 30 Ge V is measured for different regions of the Z boson’s $$p_{\\textrm{T}} (\\text {Z })$$ p T ( Z ) , from lower than 10 $$\\,\\text {Ge}\\hspace{-.08em}\\text {V}$$ Ge V to higher than 100 $$\\,\\text {Ge}\\hspace{-.08em}\\text {V}$$ Ge V . The azimuthal correlation $$\\varDelta \\phi $$ Δ ϕ between the Z boson and the leading jet, as well as the correlations between the two leading jets are measured in three regions of $$p_{\\textrm{T}} (\\text {Z })$$ p T ( Z ) . The measurements are compared with several predictions at leading and next-to-leading orders, interfaced with parton showers. Predictions based on transverse-momentum dependent parton distributions and corresponding parton showers give a good description of the measurement in the regions where multiple parton interactions and higher jet multiplicities are not important. The effects of multiple parton interactions are shown to be important to correctly describe the measured spectra in the low $$p_{\\textrm{T}} (\\text {Z })$$ p T ( Z ) regions.

The strongest constraint on Vtb presently comes from the 3×3 unitarity of the CKM matrix, which fixes Vtb to be very close to one. If unitarity is relaxed, current information from top production at Tevatron still leaves open the possibility that Vtb is sizably smaller than one. In minimal extensions of the standard model with extra heavy quarks, the unitarity constraints are much weaker, and the EW precision parameters entail the strongest bounds on Vtb. We discuss the experimental perspectives of discovering and identifying such new physics models at the Tevatron and the LHC, through a precise measurement of Vtb from the single top cross sections and by the study of processes where the extra heavy quarks are produced.

High titres of pertussis toxin (PT) antibody have been shown to be predictive of recent infection with Bordetella pertussis. The seroprevalence of standardized anti-PT antibody was determined in six Western European countries between 1994 and 1998 and related to historical surveillance and vaccine programme data. Standardized anti-PT titres were calculated for a series of whole-cell and acellular pertussis vaccine trials. For the serological surveys, high-titre sera (>125 units/ml) were distributed throughout all age groups in both high- (>90%) and low-coverage (<90%) countries. High-titre sera were more likely in infants in countries using high-titre-producing vaccines in their primary programme (Italy, 11·5%; Western Germany, 13·3%; France, 4·3%; Eastern Germany, 4·0%) compared to other countries (The Netherlands, 0·5%; Finland, 0%). Recent infection was significantly more likely in adolescents (10–19 years old) and adults in high-coverage countries (Finland, The Netherlands, France, East Germany), whereas infection was more likely in children (3–9 years old) than adolescents in low-coverage (<90%; Italy, West Germany, United Kingdom) countries. The impact and role of programmatic changes introduced after these surveys aimed at protecting infants from severe disease by accelerating the primary schedule or vaccinating older children and adolescents with booster doses can be evaluated with this approach.

Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300 fb−1 of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10 fb−1 of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, the Working Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discovered by the LHC. Their reports provide the particle physics community with some tools for reviewing the scientific priorities for future colliders after the LHC produces its first harvest of new physics from multi-TeV collisions.

In a bacterium like Helicobacter pylori, which is characterized by a recombinant population structure, the associated presence of genes encoding virulence factors might be considered an expression of a selective advantage conferred to strains with certain genotypes and, therefore, a potentially useful tool for predicting the clinical outcome of infections. However, differences in the geographical and ethnic prevalence of the H. pylori virulence-associated genotypes can affect their clinical predictive value and need to be considered in advance. In this study we carried out such an evaluation in a group of patients living in Sicily, the largest and most populous island in the Mediterranean Sea. cagA, vacA, babA2, hopQ, oipA, sabA, and hopZ were the H. pylori virulence-associated genes assayed; their presence, expression status or allelic homologs were detected in H. pylori DNA samples and/or isolated strains, obtained by gastric biopsy from 90 Sicilian patients with chronic gastritis, inactive (n = 37), active (n = 26), or active with peptic ulcer (n = 27). Genotypes cagA ⁺, vacAs1, vacAm1, babA2 ⁺, and hopQ I, I/II were identified in 51.8, 80.4, 35.2, 47.3, and 67.7% of the different samples respectively. Only these genotypes were associated with each other and with the active form of chronic gastritis, irrespective of the presence of a peptic ulcer. In our isolates their prevalence was more similar to values observed in the north of Italy and France than to those observed in Spain or other Mediterranean countries that are closer and climatically more similar to western Sicily.

This chapter of the “Flavor in the era of LHC” workshop report discusses flavor-related issues in the production and decays of heavy states at the LHC at high momentum transfer Q , both from the experimental and the theoretical perspective. We review top quark physics, and discuss the flavor aspects of several extensions of the standard model, such as supersymmetry, little Higgs models or models with extra dimensions. This includes discovery aspects, as well as the measurement of several properties of these heavy states. We also present publicly available computational tools related to this topic.

A standardisation process was developed in order to compare and harmonise serological results of pertussis toxin (PT) antibody measurements performed by laboratories using different technical procedures for detection. This involved the development of a common panel, of sera by a designed reference centre, the distribution of the panel to each participating laboratory for testing with their routine methods, the comparison of the obtained results to those of the reference centre, and the calculation of standardisation equations by regressing the quantitative results against those of the reference centre. As a cut-off indicative of protection against pertussis has not yet been defined, a particular emphasis was laid upon achieving standardisation of high titre results that would allow epidemiological evaluations based on the estimation of the incidence of recent infections rather than on the traditional approach of determining the population immunity profile. A generally good agreement was achieved between the participating laboratories, all using ELISA procedures very similar in many crucial aspects, and standardisation equations were produced useful to enable inter-country comparison during the next stages of the European Sero-Epidemiology Network (ESEN) project concerning the serological surveillance of immunity to pertussis in Europe.

Reported here is the case of a 6-week-old female infant with a severe Bordetella pertussis infection requiring supportive pressure-positive ventilation in the intensive care unit. After being discharged from the intensive care unit, she developed hemolytic anemia, thrombocytopenia and acute renal failure, which suggested a diagnosis of hemolytic uremic syndrome. The clinical outcome was favorable with no renal consequences. This case suggests there may be a direct cause-effect relationship between B. pertussis infection and hemolytic uremic syndrome.