Earliest datable records of aurora-like phenomena in the astronomical diaries from Babylonia.

The astronomical diaries from Babylonia (ADB) are excellent sources of information of natural phenomena, including astronomical ones, in pre-Christ era because it contains the record of highly continuous and systematic observations. In this article, we present results of a survey of aurora-like phenomena in ADB, spanning from BCE 652 to BCE 61. We have found nine records of aurora-like phenomena. Philological and scientific examinations suggest that five of them can be considered as likely candidate for aurora observations. They provide unique information about the solar and aurora activities in the first millennium BCE. Graphical abstract.

[Usefulness of rapid cytological diagnosis at autopsy].

The aim of this study was to evaluate the diagnostic value of rapid cytological examinations at autopsy. Rapid cytological diagnosis was performed for nine cases at autopsy using Papanicolaou and/or Giemsa staining. Material was obtained by imprint or needle-aspiration. Among 9 cases, 5 cases were sarcoma, 3 cases carcinoma and 1 case infectious disease. All cases were reported to the physicians during autopsies. Precise medical informations including rapid cytological examination were informed immediately to bereaved family members. The present study showed that rapid cytological examination in conjunction with autopsy is an easy procedure and is not only useful in the concrete diagnosis of death by unknown causes but also helpful in deciding appropriate management of materials for the next steps such as electron microscope diagnosis.

Filamentary structure on the Sun from the magnetic Rayleigh-Taylor instability.

Magnetic flux emerges from the solar surface as dark filaments connecting small sunspots with opposite polarities. The regions around the dark filaments are often bright in X-rays and are associated with jets. This implies plasma heating and acceleration, which are important for coronal heating. Previous two-dimensional simulations of such regions showed that magnetic reconnection between the coronal magnetic field and the emerging flux produced X-ray jets and flares, but left unresolved the origin of filamentary structure and the intermittent nature of the heating. Here we report three-dimensional simulations of emerging flux showing that the filamentary structure arises spontaneously from the magnetic Rayleigh-Taylor instability, contrary to the previous view that the dark filaments are isolated bundles of magnetic field that rise from the photosphere carrying the dense gas. As a result of the magnetic Rayleigh-Taylor instability, thin current sheets are formed in the emerging flux, and magnetic reconnection occurs between emerging flux and the pre-existing coronal field in a spatially intermittent way. This explains naturally the intermittent nature of coronal heating and the patchy brightenings in solar flares.