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Cosmogenic nuclides in tree rings and polar ice cores record the information of past cosmic ray intensities and solar activities. A large 14C increase over 10 years has been discovered around 5480 BCE. The 14C variations in this event differ from those of other short‐term cosmic ray events and typical grand solar minima. To elucidate the cause of the 14C increase around 5480 BCE, we measured the 10Be and 36Cl concentrations in the Antarctic Dome Fuji ice core at quasi‐annual and 4–5 years resolutions, respectively. Based on the combined 14C, 10Be, and 36Cl data, the 5480 BCE event was probably not caused by a solar proton event (SPE) or a gamma‐ray event, because the 36Cl concentration did not significantly increase as expected in these events. The incremented 10Be data were enhanced similarly to those of recent grand solar minima, but more rapidly increased (over ∼10 years). These results suggest that an unusual grand solar minimum occurred around 5480 BCE, characterized by a rapidly decreasing solar activity. Key Points: New high‐resolution 10Be and 36Cl data for the 5480 BCE cosmic ray event were taken from the Antarctic Dome Fuji ice coreMeasured 36Cl/10Be ratio was not suitable for either solar proton event or gamma‐ray event originsThe 5480 BCE event might refer to the unusual grand solar minimum which solar activity decreased rapidly in ∼10 years [ABSTRACT FROM AUTHOR]

Cosmogenic nuclides are good indicators of past cosmic ray events and variations. To verify such phenomena, it is important to evaluate them using multiple nuclides from different archives. The cosmic ray event in 993–994 Common Era (CE) has already been confirmed with 14C and 10Be data, which show rapid increases in the concentrations. However, the 10Be data were obtained from the Greenland ice cores in the Northern Hemisphere. To investigate the extent of the 10Be increase in the Southern Hemisphere, we measured quasi‐annual 10Be concentrations between 980 and 1,011 CE in the Antarctic Dome Fuji ice core. We observed a ~50% increase in 10Be concentration around 994 CE, consistent with the Greenland data. Increases in 10Be concentrations in both hemispheres support a solar origin of the 994‐CE event. In addition, we propose a method of evaluating the so‐called "system effect" for 10Be deposition by extracting common components from 10Be and Na+ data. Plain Language Summary: New quasi‐annual beryllium‐10 measurements were made with the Dome Fuji ice core from Antarctica over the period in which the 994 cosmic ray event would be expected. We observed an approximately 50% increase in beryllium‐10 concentrations, which is consistent with the beryllium‐10 increases observed in the Greenland ice cores. This lends support to a solar origin of the 994 event. We propose a phenomenological method for evaluating a common deposition component between quasi‐annual beryllium‐10 and sodium ion data. Key Points: New quasi‐annual 10Be data were taken with Antarctic Dome Fuji ice core over the period when the 994‐CE cosmic ray event took placeWe observed a ~50% increase in 10Be concentrations, which is consistent with the 10Be increases observed in the Greenland ice coresWe propose a phenomenological method for evaluating a common deposition component between quasi‐annual beryllium‐10 data and Na+ data [ABSTRACT FROM AUTHOR]

Rationale: Sulfur is widely distributed in nature, and sulfur isotopic measurements have been applied to elucidate the origin and transport of sulfuric compounds in the lithosphere, biosphere, and atmosphere. Analyses of samples containing small amounts of sulfur, such as the Antarctic ice core samples analyzed herein, require a high-sensitivity analytical method., Methods: We developed a high-sensitivity sulfur isotopic ratio (δ 34 S value) analytical system equipped with an elemental analyzer, a cryo-flow device, and an isotope ratio mass spectrometer, and established a measurement and calibration procedure., Results: Using this system, we precisely measured the δ 34 S values of samples containing 5-40 nmol sulfate. Test runs were performed on samples from the Antarctic shallow ice core DF01, and the data obtained were consistent with those obtained by previous studies that reported δ 34 S values for Antarctic snow and ice samples of more than 200 g (containing more than 150 nmol sulfate). Among the analyzed samples, one showed a peak sulfate concentration in its depth profile that is considered to have resulted from a large volcanic eruption. The δ 34 S value obtained at that depth in the sample was distinct from values at other depths and consistent with reported values for volcanic sulfates., Conclusions: The analytical system developed herein is a powerful tool for trace sulfur isotopic analyses. The results obtained from the DF01 ice core samples are the first step towards elucidating high-time-resolution (less than 1 year) paleo-environmental changes by sulfur isotopic analyses., (© 2018 John Wiley & Sons, Ltd.)

Auditory brainstem implant (ABI) is a central prosthesis that directly stimulates the cochlear nucleus in the brainstem for those who have interrupted auditory nerves and cannot benefit from the cochlear implantation. Speech perception in a recipient of the Nuclues 8 channel ABI, the first in Japan, is reported. A 25-year-old man with bilateral acoustic nerve tumors postlingually deafened due to tumor resection received auditory sensations with 5 channels. The correct answer using a coding strategy, SPEAK, was 35% for 5 vowels and 36% for 5 monosyllables. The use of ABI also improved his lip-reading ability on monosyllables and open-set words. This indicated that he benefited from ABI, although it was limited. Even after 1 year and 3 months of follow-up, he had no serious side effects such an infection or implant rejection.

An 84-year-old man was referred to our hospital because of fever, cough, and hemoptysis. The patient had acute respiratory failure (PaO2 < 40 mmHg) on admission, with diffuse interstitial infiltration and bilateral pleural effusion. The bronchoalveolar lavage fluid was bloody, and contained a high percentage of eosinophils (32%). A diagnosis of acute eosinophilic pneumonia was established, and the patient made a rapid recovery after corticosteroids were administered. When the DLST (drug lymphocyte stimulation test) was performed after the corticosteroid therapy was stopped, it was positive for serrapeptase, which had been prescribed for chronic cystitis for 3 months before the onset of the pneumonia. This was a case of drug (serrapeptase)-induced pneumonitis manifesting as acute eosinophilic pneumonia.