Phagocytic removal of cells undergoing apoptosis is necessary for animal development and tissue homeostasis. Draper, a homologue of the Caenorhabditis elegans phagocytosis receptor CED‐1, is responsible for the phagocytosis of apoptotic cells in Drosophila, but its ligand presumably present on apoptotic cells remains unknown. An endoplasmic reticulum protein that binds to the extracellular region of Draper was isolated. Loss of this protein, which we name Pretaporter, led to a reduced level of apoptotic cell clearance in embryos, and the overexpression of pretaporter in the mutant flies rescued this defect. Results from genetic analyses suggested that Pretaporter functionally interacts with Draper and the corresponding signal mediators. Pretaporter was exposed at the cell surface after the induction of apoptosis, and cells artificially expressing Pretaporter at their surface became susceptible to Draper‐mediated phagocytosis. Finally, the incubation with Pretaporter augmented the tyrosine‐phosphorylation of Draper in phagocytic cells. These results collectively suggest that Pretaporter relocates from the endoplasmic reticulum to the cell surface during apoptosis to serve as a ligand for Draper in the phagocytosis of apoptotic cells.

The scientific and technical advances continue to support novel discoveries by allowing scientists to acquire new insights into the structure and properties of matter using new tools and sources. Notably, neutrons are among the most valuable sources in providing such a capability. At the Institute of Laser Engineering, Osaka, the first steps are taken towards the development of a table-top laser-driven neutron source, capable of producing a wide range of energies with high brightness and temporal resolution. By employing a pure hydrogen moderator, maintained at cryogenic temperature, a cold neutron ($$\le 25\hbox { meV}$$ ≤ 25 meV ) flux of $$\sim 2\times 10^3\hbox { n/cm}^2$$ ∼ 2 × 10 3 n/cm 2 /pulse was measured at the proximity of the moderator exit surface. The beam duration of hundreds of ns to tens of $$\upmu \hbox {s}$$ μ s is evaluated for neutron energies ranging from 100s keV down to meV via Monte-Carlo techniques. Presently, with the upcoming J-EPoCH high repetition rate laser at Osaka University, a cold neutron flux in orders of $$\sim 1\times 10^{9}\hbox { n/cm}^2/\hbox {s}$$ ∼ 1 × 10 9 n/cm 2 / s is expected to be delivered at the moderator in a compact beamline.

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A magnetic field drift, gradual decrease of the order of 10−4 in several tens of hours, was observed with the beam intensity decrease in an operation of an azimuthally varying field (AVF) cyclotron. From our experimental results, we show that the temperature increase of the magnet iron by the heat transfer from the excitation coils can induce such change of the magnetic field as to deteriorate the beam quality. The temperature control of the magnet iron was realized by thermal isolation between the main coil and the yoke and by precise control of the cooling water temperature of the trim coils attached to the pole surfaces in order to prevent temperature change of the magnet iron. The magnetic field stability of ±5×10−6 and the beam intensity stability of ±2% have been achieved by this temperature control.

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