Assessment of the shielding efficiency of the HCLL blanket for a DEMO-type fusion reactor

International audienceThis work summarizes the results of a neutronic study on the HCLL blanket for a DEMO-type fusion reactor. The analysis is based on three-dimensional Monte Carlo calculations using the MCNP-4C code. It comprises the assessment of the shielding efficiency in terms of the radiation loads to the superconducting TF-coils and the neutron induced production of He and H gas in the steel structure of the blanket and at locations where the welding of pipe connections is assumed. The analysis is performed utilizing three-dimensional 9$^0$-sector model representing the modular HCLL breeder blanket developed by CEA. The shielding performance of the blanket/shield/vacuum vessel system is assessed at the torus mid-plane considering three variants of a two-component shield, arranged in between the central inboard modules and the Vacuum Vessel. Estimates of radial distributions of the He and H gas production in the steel structure of the blanket are obtained and the radial depth where the re-weldability criterion for the He production <1 appm is fulfilled is identified

Subsets of T regulatory cells in patients with IgE-mediated allergy

Background. It is presently known that several subsets of T-regulatory (Treg) cells, both natural and inducible maintain tolerance to environmental allergens. But the relative importance of distinct phenotypically defined Treg subsets for the clinical manifestations of IgE-mediated allergy has not been elucidated yet.The aim of the study was to investigate the phenotype and number of different Treg subpopulations from patients with IgE-mediated allergy compared with healthy non-allergic individuals.Materials and methods. A group of 20 patients with clinically manifested IgE allergy and a group of 10 healthy no allergic controls were included in the study. Peripheral blood samples were taken after informed consent. Percentage and absolute count (AC) of the following regulatory subsets: naive (CD45RO-FoxP3lo), memory (RO+FoxP3+), effector (Treg eff, RO+FoxP3hi), induced (CD39+CD134+), Thl7/Treg (CD196+FoxP3+CD4Treg); Tr1 (IL-10+FoxP3-), were determined using standard 8-parameter flow cytometry (BD FACSCanto II).Results and discussion. The share and AC of FoxP3+CD4 Treg was significantly decreased in sensitized patients as compared to controls (mean 0,6% vs. 3,3%, p&lt;0.05 and 8,7 vs. 55 cells/μl p&lt;0.001). In addition, a significantly decreased level of Tr1 cells was observed in the patients with allergy, 0,4% vs. 2,1 % in healthy controls (p&lt;0,05) as well for subset of Thl7/Treg (mean 7,7% vs. 28,4% in healthy persons, p&lt;0.01).Conclusion. The significantly decreased number of FoxP3+CD4 Treg as well as periphery induced Tr1 and Thl7/Treg cells in patients with respiratory allergy lead to dysregulation and loss of peripheral immune tolerance, which is the pathophysiological basis for development of widely spread allergic diseases like allergic rhinitis and bronchial asthma