Search

We continue our study of strongly-coupled, approximately scale-invariant gauge theories with a large number of flavours, which provide a suitable ultraviolet completion of the composite-Higgs scenario. We identify the requisite operators to realise partial compositeness of the Standard-Model fermions. In order to compute the spectrum of composite fermionic states, we extend the bottom-up holographic models, which we previously introduced to capture the main features of the non-perturbative dynamics in the Veneziano limit, by adding fermion fields in the bulk. We identify regions in parameter space where some fermionic bound states become light, depending in particular on the number of flavours, the operator scaling dimensions, and the bulk Yukawa couplings. We also observe a dense spectrum of states, when multi-scale dynamics is induced by a large backreaction of bulk scalars on the geometry. Adapting the formalism of the holographic Wilsonian renormalisation group, we study the linear coupling between the composite and elementary fermions, as a function of energy scale. We find that, in some circumstances, the associated operators are dangerously irrelevant: the renormalisation-group flow gives rise to a large linear coupling in the infrared, even when it is irrelevant from the point of view of the ultraviolet fixed point. We finally compute the partially composite spectrum, correlate it with the analysis of the flow, and assess the potential phenomenological implications, e.g. for the top-quark partners.

We investigate new-physics contributions to $b\to s \ell\ell$ transitions in the context of an effective field theory extension of the Standard Model, including operator mixing at one loop. We identify the few scenarios where a single Wilson coefficient, $C/\Lambda^2 \sim 1/{\rm TeV}^2$, induces a substantial shift in the lepton flavour universality ratios $R_K$ and $R_{K^*}$ at one loop, while evading $Z$-pole precision tests, collider bounds, and other flavour constraints. Good fits to the present data are achieved by a left-handed current operator with quark-flavour indices $(2,2)$ or $(3,3)$, hitherto overlooked. Interestingly, the running of the Standard Model Yukawa matrices gives the dominant effect for these scenarios. We match the favoured effective-theory scenarios to minimal, single-mediator models, which are subject to additional stringent constraints. Notably, we recognise three viable instances of a leptoquark with one coupling to fermions only. If the anomalies were confirmed, it appears that one-loop explanations have good prospects of being directly tested at the LHC., Comment: v2: 15 pages, 6 figures; Section III.2 extended, Table II and Fig. 6 correspondingly updated, references added

International audience; I discuss the infrared mass spectrum of strongly-coupled gauge theories, thatinduce the Higgs as a composite pseudo-Nambu-Goldstone boson. The set ofcomposite states accompanying the Higgs is determined by the symmetries of thetheory. Here we estimate their mass spectrum by non-perturbative techniquesinspired by QCD, as well as by exploiting gauge-gravity duality. 1 CompositeHiggs: motivations and relevant energy scales As the Large Hadron Collider (LHC)did not find new states significantly coupled to the Standard Model (SM) belowthe TeV scale, any SM extension by such heavy states suffers from a littlehierarchy problem, as the mass of the scalar Higgs boson lies close to the 100GeV scale. Still, some SM extensions have the potential to address the bighierarchy between the TeV scale and the Planck scale. One possibility is toavoid elementary scalar fields, and assume the observed Higgs is a compositeobject, with a compositeness scale f 1 TeV. This scenario requires a strongly-coupled sector, whose spectrum generically includes several additional compositestates besides the Higgs. The mass of the lowest-lying states cannot exceed ∼4πf , and some could be significantly lighter and within the LHC reach. Definitepredictions for the mass spectrum require to specify the strongly-coupled theoryin the ultraviolet (UV). Here we will assume it is a gauge theory of fermions,that confines in the infrared. We will estimate its mass spectrum in some well-defined approximations, by employing non-perturbative techniques inspired by QCD1) , as well as gauge-gravity duality techniques 2). In models where the Higgsis a pseudo-Nambu-Goldstone boson (pNGB) the electroweak scale, v 246 GeV, isinduced in two steps. The theory has a global (flavour) symmtry G F , that isspontaneously broken to a subgroup H F at the scale f. The electroweak symmetrySU (2) L × U (1) Y is embedded in 91

Background and Purpose— As a reliable scoring system to detect the risk of symptomatic intracerebral hemorrhage after thrombectomy for ischemic stroke is not yet available, we developed a nomogram for predicting symptomatic intracerebral hemorrhage in patients with large vessel occlusion in the anterior circulation who received bridging of thrombectomy with intravenous thrombolysis (training set), and to validate the model by using a cohort of patients treated with direct thrombectomy (test set). Methods— We conducted a cohort study on prospectively collected data from 3714 patients enrolled in the IER (Italian Registry of Endovascular Stroke Treatment in Acute Stroke). Symptomatic intracerebral hemorrhage was defined as any type of intracerebral hemorrhage with increase of ≥4 National Institutes of Health Stroke Scale score points from baseline ≤24 hours or death. Based on multivariate logistic models, the nomogram was generated. We assessed the discriminative performance by using the area under the receiver operating characteristic curve. Results— National Institutes of Health Stroke Scale score, onset-to-end procedure time, age, unsuccessful recanalization, and Careggi collateral score composed the IER-SICH nomogram. After removing Careggi collateral score from the first model, a second model including Alberta Stroke Program Early CT Score was developed. The area under the receiver operating characteristic curve of the IER-SICH nomogram was 0.778 in the training set (n=492) and 0.709 in the test set (n=399). The area under the receiver operating characteristic curve of the second model was 0.733 in the training set (n=988) and 0.685 in the test set (n=779). Conclusions— The IER-SICH nomogram is the first model developed and validated for predicting symptomatic intracerebral hemorrhage after thrombectomy. It may provide indications on early identification of patients for more or less postprocedural intensive management.

Background- Thrombectomy of acute ischemic stroke requires changes to acute stroke services since most hospitals do not have on-site thrombectomy facilities. We aimed to compare two different models in use in eastern Lombardy (Italy).Methods u2013 We compared process performance (onset-to-groin puncture times), clinical (survival and functional outcome at discharge) and radiological outcomes (status of the occluded artery after recanalization therapy) under two different models: the u201cdrip-and-shipu201d (patient transport to hub after intravenous thrombolytic treatment in spoke) and the u201cmobile interventionalistu201d (interventionalist moves from the hub to the spoke, to carry out thrombectomy). The two models were used in two different hospitals depending on the same hub. Results u2013 A total of 75 patients with acute ischemic stroke was treated with thrombectomy from January 2017 to December 2018: 39 under the u201cmobile interventionalistu201d model and 36 under the u201cdrip-and-shipu201d model (Table). The u201cmobile interventionalistu201d model allowed to initiate thrombectomy more than 2 hours earlier (p=0.009), however, clinical and radiological outcomes were similar in the two models. Conclusion u2013 In hospitals without on-site interventionalist, the u201cmobile interventionalistu201d model as compared to the u201cdrip-and-shipu201d model, can reduce onset-to-groin puncture times. Further studies to assess the clinical efficacy of this model are warranted.

Status of lepton physics as of 2015; National audience

International audience; I will argue that pseudo Nambu-Goldstone bosons (pNGBs) may be natural candidates for the dark matter (DM). I will present two scenarios where the mass and the interactions of the pNGBs are connected to the electroweak scale. In this case the DM properties are interlaced with the properties of the Higgs boson. The computation of the DM relic density and the detection perspectives will be discussed.

International audience; We investigate grand unified theories (GUTs) in scenarios where electroweak (EW) symmetry breaking is triggered by a light composite Higgs, arising as a Nambu-Goldstone boson from a strongly interacting sector. The evolution of the standard model (SM) gauge couplings can be predicted at leading order, if the global symmetry of the composite sector is a simple group G that contains the SM gauge group. It was noticed that, if the right-handed top quark is also composite, precision gauge unification can be achieved. We build minimal consistent models for a composite sector with these properties, thus demonstrating how composite GUTs may represent an alternative to supersymmetric GUTs. Taking into account the new contributions to the EW precision parameters, we compute the Higgs effective potential and prove that it realizes consistently EW symmetry breaking with little fine-tuning. The G group structure and the requirement of proton stability determine the nature of the light composite states accompanying the Higgs and the top quark: a coloured triplet scalar and several vector-like fermions with exotic quantum numbers. We analyse the signatures of these composite partners at hadron colliders: distinctive final states contain multiple top and bottom quarks, either alone or accompanied by a heavy stable charged particle, or by missing transverse energy.

Made available in DSpace on 2013-08-12T18:38:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-01 Made available in DSpace on 2013-09-30T18:08:37Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:22:32Z No. of bitstreams: 0 Made available in DSpace on 2014-05-20T13:22:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-01 OBJETIVOS: Investigar, de forma integrada, possíveis indicadores de alterações cognitivas, depressão, ansiedade e agentes estressores ocupacionais em auxiliares e técnicos de enfermagem e enfermeiros de diversos setores da Santa Casa de Misericórdia de Assis-SP, por meio de instrumentos de rastreio psicológico e cognitivo. MÉTODOS: Participaram do estudo 66 profissionais de enfermagem, avaliados por instrumentos de rastreio psicológico e cognitivo. RESULTADOS: A experiência de estresse não foi homogênea na equipe de enfermagem; escores altos no rastreio de depressão foram associados a escores cognitivos baixos. CONCLUSÃO: Auxiliares e técnicos de enfermagem e enfermeiros foram afetados pelo estresse, portanto, atenção à saúde do trabalhador deve ser oferecida a toda a equipe de enfermagem. Objective: Investigating the indicators of stress, anxiety, depression and the cognitive changes in members of the nursing team at Santa Casa de Misericordia de Assis - SP. Methods: 66 nursing professionals participated in the study, evaluated by psychological and cognitive tracking instruments. Results: The stress experience was not homogenous in the nursing team; high scores in the depression tracking were associated to low cognitive scores. Conclusion: Nursing auxiliaries and technicians were affected by stress. Therefore, workers healthcare should be provided for the whole nursing team. Univ Estadual Paulista, Grad Psychol Dept, Assis, SP, Brazil Univ Estadual Paulista, Grad Psychol Dept, Assis, SP, Brazil

International audience; We discuss a source of light neutrino masses and leptogenesis in SO(10) unification theories, that was not previously recognized. It is present when the light lepton doublets belong (at least partially) to dimension‐10 matter multiplets. At odds with previous leptogenesis scenarios, the CP asymmetry depends only on the low energy flavour parameters of the neutrino sector. We demonstrate that a successful generation of the baryon asymmetry of the Universe is possible.

The smallness of the 1-3 lepton mixing angle $��_{13}$ and of the neutrino mass-squared-difference ratio $��m^2_{12}/��m^2_{23}$ can be understood as the departure from a common limit where they both vanish. We discuss in general the conditions for realizing the mass degeneracy of a pair of neutrinos and show that the vanishing of a CP violating phase is needed. We find that the discrete quaternion group Q of eight elements is the simplest family symmetry which correlates the smallness of $��m^2_{12}$ to the value of $��_{13}$. In such a model we predict $0.12\lesssim \sin��_{13} \lesssim 0.2$ if the ordering of the neutrino mass spectrum is normal, and $\sin��_{13}\lesssim 0.12$ if it is inverted., revtex, 7 pages, 6 pdf figures; Appendix added discussing in detail the alignment of VEVs