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The boron-10 based multi-grid detector is being developed as an alternative to helium-3 based neutron detectors. At the European Spallation Source, the detector will be used for time-of-flight neutron spectroscopy at cold to thermal neutron energies. The objective of this work is to investigate fine time- and energy-resolved effects of the Multi-Grid detector, down to a few µeV, while comparing it to the performance of a typical helium-3 tube. Furthermore, it is to characterize differences between the detector technologies in terms of internal scattering, as well as the time reconstruction of ∼ µs short neutron pulses. The data were taken at the Helmholtz Zentrum Berlin, where the Multi-Grid detector and a helium-3 tube were installed at the ESS test beamline, V20. Using a Fermi-chopper, the neutron beam of the reactor was chopped into a few tens of µs wide pulses before reaching the detector, located a few tens of cm downstream. The data of the measurements show an agreement between the derived and calculated neutron detection efficiency curve. The data also provide fine details on the effect of internal scattering, and how it can be reduced. For the first time, the chopper resolution was comparable to the timing resolution of the Multi-Grid detector. This allowed a detailed study of time- and energy resolved effects, as well as a comparison with a typical helium-3 tube. [ABSTRACT FROM AUTHOR]

Nb3Sn magnets with a nominal operation field of ~15 T are being considered for the Large Hadron Collider (LHC) energy upgrade High-Energy Large Hadron Collider (HE-LHC) and a post-LHC future circular collider. To demonstrate the feasibility of 15-T accelerator quality dipole magnets, the U.S. magnet development program is developing a single-aperture 15-T Nb3Sn dipole demonstrator based on a 4-layer graded cos-theta coil with 60 mm aperture and cold iron yoke. The main design challenges for 15-T accelerator magnets include large Lorentz forces at this field level. To counteract them, an innovative mechanical structure based on a vertically split iron yoke, locked by large aluminum IC-clamps and supported by a thick stainless steel skin, has been developed at Fermilab. To study the performance of the structure, a parametric multiphysics finite element analysis (FEA) model has been set up. This paper describes the numerical model as well as the results of a sensitivity analysis of the effect of geometrical tolerances and assembly parameters. [ABSTRACT FROM AUTHOR]

Primary effusion lymphoma (PEL) is a unique form of non-Hodgkin lymphoma, mainly met in severely immunocompromised, HIV-positive patients. PEL is aetiologically related to human herpes virus-8 (HHV-8) and it usually presents as a lymphomatous body cavity effusion in the absence of a solid tumour mass. Recently, cases of HIV-positive patients with HHV-8- positive solid tissue lymphomas, not associated with an effusion, have been reported (solid variant of PEL). The prognosis of PEL is reported to be poor. We report a case of an HIV-positive patient with a typical solid variant of PEL without effusion. Interestingly, his disease developed while being on stable antiretroviral therapy (ART) with high CD4 counts. He had a relatively long survival with chemotherapy and ART. [ABSTRACT FROM AUTHOR]