A new surgical model of skeletal muscle injuries in rats reproduces human sports lesions

Skeletal muscle injuries are the most common sports-related injuries in sports medicine. In this work, we have generated a new surgically-induced skeletal muscle injury in rats, by using a biopsy needle, which could be easily reproduced and highly mimics skeletal muscle lesions detected in human athletes. By means of histology, immunofluorescence and MRI imaging, we corroborated that our model reproduced the necrosis, inflammation and regeneration processes observed in dystrophic mdx-mice, a model of spontaneous muscle injury, and realistically mimicked the muscle lesions observed in professional athletes. Surgically-injured rat skeletal muscles demonstrated the longitudinal process of muscle regeneration and fibrogenesis as stated by Myosin Heavy Chain developmental (MHCd) and collagen-I protein expression. MRI imaging analysis demonstrated that our muscle injury model reproduces the grade I-II type lesions detected in professional soccer players, including edema around the central tendon and the typically high signal feather shape along muscle fibers. A significant reduction of 30% in maximum tetanus force was also registered after 2 weeks of muscle injury. This new model represents an excellent approach to the study of the mechanisms of muscle injury and repair, and could open new avenues for developing innovative therapeutic approaches to skeletal muscle regeneration in sports medicin

Search for black holes and other new phenomena in high-multiplicity final states in proton-proton collisions at root s=13 TeV

Peer reviewe

Search for high-mass diphoton resonances in proton-proton collisions at 13 TeV and combination with 8 TeV search

Peer reviewe

Search for heavy resonances decaying into a vector boson and a Higgs boson in final states with charged leptons, neutrinos, and b quarks

Peer reviewe

Performance of reconstruction and identification of τ leptons decaying to hadrons and vτ in pp collisions at √s=13 TeV

The algorithm developed by the CMS Collaboration to reconstruct and identify τ leptons produced in proton-proton collisions at √s=7 and 8 TeV, via their decays to hadrons and a neutrino, has been significantly improved. The changes include a revised reconstruction of π⁰ candidates, and improvements in multivariate discriminants to separate τ leptons from jets and electrons. The algorithm is extended to reconstruct τ leptons in highly Lorentz-boosted pair production, and in the high-level trigger. The performance of the algorithm is studied using proton-proton collisions recorded during 2016 at √s=13 TeV, corresponding to an integrated luminosity of 35.9 fb¯¹. The performance is evaluated in terms of the efficiency for a genuine τ lepton to pass the identification criteria and of the probabilities for jets, electrons, and muons to be misidentified as τ leptons. The results are found to be very close to those expected from Monte Carlo simulation

Search for single production of a heavy vector-like T quark decaying to a Higgs boson and a top quark with a lepton and jets in the final state

A search for single production of vector-like top quark partners (T) decaying into a Higgs boson and a top quark is performed using data from pp collisions at a centre-of-mass energy of 13 TeV collected by the CMS experiment at the CERN LHC, corresponding to an integrated luminosity of 2.3 fb−1. The top quark decay includes an electron or a muon while the Higgs boson decays into a pair of b quarks. No significant excess over standard model backgrounds is observed. Exclusion limits on the product of the production cross section and the branching fraction are derived in the T quark mass range 700 to 1800 GeV. For a mass of 1000 GeV, values of the product of the production cross section and the branching fraction greater than 0.8 and 0.7 pb are excluded at 95% confidence level, assuming left- and right-handed coupling of the T quark to standard model particles, respectively. This is the first analysis setting exclusion limits on the cross section of singly produced vector-like T quarks at a centre-of-mass energy of 13 TeV

Search for heavy resonances decaying to a top quark and a bottom quark in the lepton+jets final state in proton–proton collisions at 13 TeV

A search is presented for narrow heavy resonances decaying to a top quark and a bottom quark using data collected by the CMS experiment at √s = 13TeV in 2016. The data set analyzed corresponds to an integrated luminosity of 35.9 fb−1. Final states that include a single lepton (e, μ), multiple jets, and missing transverse momentum are analyzed. No evidence is found for the production of a W′ boson, and the production of right-handed W′ bosons is excluded at 95% confidence level for masses up to 3.6 TeV depending on the scenario considered. Exclusion limits for W′ bosons are also presented as a function of their coupling strength to left- and right-handed fermions. These limits on a W′ boson decaying via a top and a bottom quark are the most stringent published to date

Measurement of angular parameters from the decay B⁰ → K⁎0^{⁎0} μ⁺ μ⁻ in proton–proton collisions at √s 8 TeV

Angular distributions of the decay B⁰  → K$^{⁎0}$ μ⁺ μ⁻ are studied using a sample of proton–proton collisions at √s=8TeV collected with the CMS detector at the LHC, corresponding to an integrated luminosity of 20.5fb⁻¹ . An angular analysis is performed to determine the P₁ and P$^{\u27}$₅ parameters, where the P$^{\u27}$₅ parameter is of particular interest because of recent measurements that indicate a potential discrepancy with the standard model predictions. Based on a sample of 1397 signal events, the P₁ and P$^{\u27}$₅ parameters are determined as a function of the dimuon invariant mass squared. The measurements are in agreement with predictions based on the standard model