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X-Ray Imaging and Spectroscopy Mission (XRISM) is the seventh Japanese X-ray astronomical satellite scheduled to be launched in the Japanese fiscal year 2022. XRISM has two mission instruments, “Resolve”, a soft X-ray spectrometer, and “Xtend”, a soft X-ray imager. The Former is an X-ray micro-calorimeter that has ∼ 5 eV of energy resolution with 3′ × 3 ′ of field of view. The Latter is an X-ray CCD camera with 38′ × 38′ of field of view. Both instruments are placed on the focal plane of X-ray telescopes, X-ray Mirror Assembly (XMA). Xtend CCDs are designed almost the same as those of Hitomi (ASTRO-H), whereas some improvements have been applied. In 2019, flight-model (FM) candidates of Xtend CCDs were fabricated by Hamamatsu Photonics K.K. We performed screening experiments to examine whether they met requirements or not, and then selected the best four chips as the FM. We then performed on-ground calibration on August 2019 and September 2019 for the FM chips to determine the gain correction parameters and to construct the detector response with several energies of monochromatic X-ray. In this paper, we report screening, selection, and on-ground calibration processes, especially focusing on the response verification.

X-ray Imaging Spectroscopy Mission (XRISM) is the next Japanese X-ray astronomical satellite to be launched in 2021 Japanese fiscal year. We are developing one of the XRISM instruments “Xtend”, which is an X-ray CCD camera combined with an X-ray telescope, and achieves the wide field of view of 3 8 ′ × 3 8 ′ in 0.4–13 keV. In 2019, twelve flight-model (FM) candidate CCD chips were fabricated by Hamamatsu Photonics K.K. We conducted screening experiments to examine whether the FM candidates met requirements for the Xtend CCDs, and selected the four FM chips from them. We constructed a screening system, with which we can examine various CCD performances by illuminating characteristic X-ray lines in a ∼ 0 . 5 –14 keV band or optical lights. With this system, all the twelve candidates were confirmed to satisfy the requirements. We then selected four chips with the best performance, in terms of e.g., their charge transfer inefficiencies, energy resolutions, soft X-ray sensitivities, and optical light leakages. In this paper, we report an overview of the screening system, and procedures and results of the screening process.

A case of extramammary Paget's disease of the perianal area adjacent to a mucinous adenocarcinoma of the rectum is presented. The histopathological examination of the case revealed that within the epidermis adjacent to the invading rectal cancer nest, the formation of glandular structures can be observed occasionally, around which so-called Paget's cells are noted to be scattered and further many points of similarity between cancer cell and Paget's cell are proved by electron microscope. Perianal skin lesion looking like Paget's disease is proved to be due to intraepidermal spread of the rectal carcinoma. Referring to the literature, this is the first report to our knowledge, to elucidate the histogenesis of perianal extramammary Paget's disease associated with a rectal carcinoma using the electron microscopy.

From our experience of malignant lymphoma in the large intestine and reviewing the Japanese literature, it might be concluded that this particular lesion was extremely rare, and was found predominantly in the right side of the colon. In contrast to the other malignant neoplasms in the large intestine, malignant lymphoma was found fairly often in children, which was accompanied by intussusception not infrequently (Table 14).