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An ion beam cooler and buncher has beendeveloped for the manipulation of radioactive ion beams. The gas-lled linear radiofrequency ion trap system is installed at the Penning trap mass spectrometer ISOLTRAP at ISOLDE/CERN. Its purpose is to accumulate the 60-keV continuous ISOLDE ion beam with high e ciency and to convert it into low-energy low-emittance ion pulses. The e ciency was found to exceed 10 % in agreement with simulations. A more than 10-fold reduction of the ISOLDE beam emittance can beachieved. The system has beenused successfully for rst on-line experiments. Its principle, setup and performance will be discussed.

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Automatic indexing of electron backscattered diffraction patterns, scanning electron microscopy, and optical microscopy observations have been carried out on aluminum-magnesium-silicon, aluminumcopper, and aluminum-silicon alloys directionally solidified or semicontinuously cast using the direct chill casting process. From these combined observations, it is shown that the feathery grains are made of ͗110͘ primary dendrite trunks (e.g., [01 ]) split in their centers by a coherent (111) twin 1 plane. The average spacing of the dendrite trunks in the twin plane (about 10 to 20 m) is typically one order of magnitude smaller than that separating successive rows of trunks (or twin planes). The [01 ] orientation of these trunks is close to the thermal gradient direction (typically within 15 deg)-1 a feature probably resulting from a growth competition mechanism similar to that occurring during normal ͗100͘ columnar dendrite growth. On both sides of these trunks, secondary dendrite arms also grow along ͗110͘ directions. Their impingement creates wavy noncoherent twin boundaries between the coherent twin planes. In the twin plane, evidence is shown that ͗110͘ branching mechanisms lead to the propagation of the twinned regions, to the regular arrangement of the primary dendrite trunks along a [ 11] direction, and to coherent planar twin boundaries. From these observations, it 2 is concluded that the feathery grains are probably the result of a change from a normal ͗100͘ to a ͗110͘ surface tension/attachment kinetics anisotropy growth mode. This change might be induced by the added solute elements, by the local solidification conditions (thermal gradient, growth rate, and melt convection), and possibly by the help of the twin plane itself. Convection in the melt could also play a role in the symmetrization of the ͗110͘ growth directions of the side arms. Finally, the proposed mechanisms of feathery grain growth are further supported by the observation of ͗110͘ dendrite growth morphologies in thin aluminum-zinc coatings.

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Coronavirus disease 2019 (COVID-19) is an infectious disease caused by a newly emerging coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 has a very variable clinical picture, ranging from asymptomatic to SARS that can lead to death.Our case, a 74-year-old female patient, presented with fever, moderate dyspnoea and leucocytosis (white blood cell count 21.6 9 10 9 /l, neutrophils 16.8 9 10 9 /l, lymphocytes 3.67 9 10 9 /l). Reverse transcriptase-polymerase chain reaction for SARS-CoV-2 was performed, which confirmed COVID-19.Peripheral blood film examination revealed a highly pleomorphic atypical lymphocyte population (right). Many cells were large (15-30 µm). The cytoplasm was sometimes granulated. Cytoplasmic basophilia was sometimes generalised and sometimes confined to the cytoplasmic margins. Some cells had one or more nucleoli and could have been mistaken for blast cells. Plasma cells and apoptotic cells were also present.In 5-10% of full blood counts of our hospitalised patients suffering from COVID-19 (all care sectors including intensive care), flags on our haematology analysers are present: 'MO Blast' for DXH800 (Beckman Coulter, top left) and 'Blasts Abn/lympho?' for XN10 (Sysmex, bottom left), requiring a blood film examination.Cytology in COVID-19 usually shows numerous neutrophils with either normal or decreased lymphocytes. This case illustrates the atypical lymphocytes that are often present. These cells morphologically mimic those of Epstein-Barr virus or cytomegalovirus infection, whereas plasma cells and plasmacytoid lymphocytes (present in some of our patients) are not usually a feature of these two infections.

Irradiation of chemically synthesized Au nanoparticles embedded in a dielectric matrix promotes the formation of a halo of satellites around the original cluster. We show that the complete dissolution of the nanoparticles (NC) results in the formation of a narrow size distribution of small precipitates with a mean size of 2 nm and a standard deviation of 0.4 nm. By combining the chemical synthesis of the nanoparticles and the irradiation to induce their dissolution and precipitation, we give a guideline method for overcoming the difficulty of controlling the size and spatial distribution of the embedded NC associated with ion implantation technique. In particular, we showed that the irradiation can be used to tailor the size of the already formed NC. Moreover, we establish that the satellites cluster evolution under irradiation can be described by a two step process. These two steps are discussed in terms of classical and inverse Ostwald ripening mechanisms.

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