Extra-osseous osteochondroma-like soft tissue mass of the patello-femoral space

BACKGROUND: Extraskeletal cartilaginous tumors are uncommon. Osteochondromas usually arise from the metaphyseal region of the growing skeleton. CASE PRESENTATION: A 53 year old man presented with a three years history of anterior knee pain and inability to flex his knee more than 90°. Clinical examination and imaging studies revealed a nodular calcific mass in the anterior portion of the knee, displacing the medial portion of the patellar tendon. Following excision, histopathology confirmed the diagnosis of extra-osseous osteochondroma-like soft tissue mass, with no recurrence 24 months after surgery. CONCLUSION: An integrated clinical-pathologic diagnosis helps to clarify the nature of extraskeletal cartilaginous tumors that can arise at unusual anatomic site. Complete local surgical excision is the management of choice

Measurement of antiproton production from antihyperon decays in p He collisions at √sNN = 110 GeV

The interpretation of cosmic antiproton flux measurements from space-borne experiments is currently limited by the knowledge of the antiproton production cross-section in collisions between primary cosmic rays and the interstellar medium. Using collisions of protons with an energy of 6.5TeV incident on helium nuclei at rest in the proximity of the interaction region of the LHCb experiment, the ratio of antiprotons originating from antihyperon decays to prompt production is measured for antiproton momenta between 12 and 110GeV. The dominant antihyperon contribution, namely Λ¯→p¯π+ decays from promptly produced Λ¯ particles, is also exclusively measured. The results complement the measurement of prompt antiproton production obtained from the same data sample. At the energy scale of this measurement, the antihyperon contributions to antiproton production are observed to be significantly larger than predictions of commonly used hadronic production models

Direct CP violation in charmless three-body decays of B± mesons

Measurements of C P asymmetries in charmless three-body decays of B ± mesons are reported using proton-proton collision data collected by the LHCb detector, corresponding to an integrated luminosity of 5.9     fb − 1 . The previously observed C P asymmetry in B ± → π ± K + K − decays is confirmed, and C P asymmetries are observed with a significance of more than five standard deviations in the B ± → π ± π + π − and B ± → K ± K + K − decays, while the C P asymmetry of B ± → K ± π + π − decays is confirmed to be compatible with zero. The distributions of these asymmetries are also studied as a function of the three-body phase space and suggest contributions from rescattering and resonance interference processes. An indication of the presence of the decays B ± → π ± χ c 0 ( 1 P ) in both B ± → π ± π + π − and B ± → π ± K + K − decays is observed, as is C P violation involving these amplitudes

Measurement of J/ψ -pair production in pp collisions at √s = 13 TeV and study of gluon transverse-momentum dependent PDFs

The production cross-section of J/ψ pairs in proton-proton collisions at a centre-of-mass energy of √s = 13 TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fb−1 collected by the LHCb experiment. The measurement is performed with both J/ψ mesons in the transverse momentum range 0 < pT< 14 GeV/c and rapidity range 2.0 < y < 4.5. The cross-section of this process is measured to be 16.36 ± 0.28 (stat) ± 0.88 (syst) nb. The contributions from single-parton scattering and double-parton scattering are separated based on the dependence of the cross-section on the absolute rapidity difference ∆y between the two J/ψ mesons. The effective cross-section of double-parton scattering is measured to be σeff = 13.1 ± 1.8 (stat) ± 2.3 (syst) mb. The distribution of the azimuthal angle ϕCS of one of the J/ψ mesons in the Collins-Soper frame and the pT-spectrum of the J/ψ pairs are also measured for the study of the gluon transverse-momentum dependent distributions inside protons. The extracted values of ⟨cos 2ϕCS⟩ and ⟨cos 4ϕCS⟩ are consistent with zero, but the presence of azimuthal asymmetry at a few percent level is allowed

Activit\ue9 potentielle de m\ue9thanogen\ue8se dans les sols, tourbi\ue8res, s\ue9diments lacustres et du r\ue9servoir hydro\ue9lectrique Robert-Bourassa dans le moyen Nord-Canadien

L\u2019immersion des sols lors de la cr\ue9ation d\u2019un r\ue9servoir hydro\ue9lectrique pourrait augmenter, au moins \ue0 court terme, le flux de m\ue9thane vers l\u2019atmosph\ue8re. Afin d\u2019\ue9valuer la contribution potentielle de tels am\ue9nagements \ue0 la production de m\ue9thane, nous avons \ue9tudi\ue9 l\u2019activit\ue9 potentielle des bact\ue9ries m\ue9thanog\ue8nes dans les sols de la for\ueat bor\ue9ale non immerg\ue9s et immerg\ue9s lors de la mise en eau d\u2019un r\ue9servoir, ainsi que des s\ue9diments lacustres. De cette \ue9tude comparative, il ressort que les tourbi\ue8res inond\ue9es p\ue9riodiquement (zone de marnage) ou en permanence, peuvent contribuer d\u2019avantage \ue0 la production de m\ue9thane que les tourbi\ue8res non inond\ue9es, les sols ou les s\ue9diments de lacs naturels. Toutefois, l\u2019intensit\ue9 et l\u2019\ue9volution temporelle de l\u2019activit\ue9 potentielle des bact\ue9ries m\ue9thanog\ue8nes dans les diff\ue9rents milieux pris en compte ont \ue9t\ue9 sous la d\ue9pendance d\u2019une combinaison de plusieurs facteurs environnementaux, notamment, la quantit\ue9 de la mati\ue8re organique, le niveau d\u2019eau et la pr\ue9sence de certains ions oxydants (SO\u2084\ub2\u207b, Fe\ub3\u207a).Flooding of land associated with the creation of reservoirs may increase, at least in the short term, methane flux to the atmosphere. To evaluate the potential contribution of such land use on methane production, field samples were studied in vitro for the potential activity of methanogenic bacteria in unflooded or flooded boreal forest soils, together with lacustrine sediments. From this comparative study, periodically flooded or flooded peats contribute more to methane production than do unflooded peats, soils, and natural lake sediment. The intensity and temporal changes in the activity of methanogenic archaea in the different systems depended on a combination of environmental factors, such as the amount and quality of organic carbon, the water level, and the concentration of oxidizing ions (SO\u2084\ub2\u207b, Fe\ub3\u207a).NRC publication: Ye