Shinmoedake (Kyushu, Japan), which is one of the Kirishima Volcanoes, experienced several small eruptions in 2010, finally culminating in a sub-plinian eruption on January 26-27, 2011. After this sub-plinian phase, the eruption style shifts to the phase of vulcanian eruption or ash emission. This volcanic activity is still occurring. We here summarize the eruption history of Shinmoedake during the Edo period on the basis of historical records. The eruptions of Shinmoedake during the Edo period occurred in AD 1716-1717 (Kyoho eruption) and AD 1822 (the 4th year of Bunsei eruption). The Kyoho eruption, which was a large-scale (total amount of tephra: 2×10¹¹ kg) eruption, is divided into the following seven stages. Stage 1 (Apr. 10, 1716 to May 7, 1716): small eruptions occurred over two months; Stage 2 (Sep. 26, 1716): falling ash first observed at the foot of Shinmoedake; Stage 3 (Nov. 9 to 10, 1716): the first large eruption was observed, with pumice falling over a wide area; Stage 4 (Dec. 4 to 6, 1716): small eruptions; Stage 5 (Feb. 9 to 20, 1717): the second pumice fall eruption, with an intermittent ash fall eruption thereafter; Stage 6 (Mar. 3, Mar. 8, Mar 13, Apr. 8, 1717): ash fall eruptions; Stage 7 (Sep. 9, 1717): the last ash fall eruption. These eruptions, which continued intermittently over 17 months, were characterized by multiple repetitions of a large eruption. Based on the results of a comparison between the Kyoho eruption and the 2011 eruption, the eruptions from March 30, 2010 to January 26, 2011, were similar to Stages 1 to 3 of the Kyoho eruption; the eruptions after January 26, 2011, were similar to Stages 5 to 6 of the Kyoho eruption. In addition, the relatively large eruption events of Stages 3 and 5 of the Kyoho eruption and the January 26-27, 2011, eruption began without any noticeable precursors. The eruption in the 4th year of Bunsei (AD 1822) was a small eruption that lasted less than a day. The recent eruption sequences, which were also similar to the Edo period eruptions, are divided into a small-scale eruption (the 1959 eruption) and a large-scale eruption (the 2011 eruption). The eruption duration time of the small-scale (total amount of tephra: ＜ 10¹⁰ kg) eruption was less than a day. The eruption duration time of the large-scale (total amount of tephra: ＞ 10¹⁰ kg) eruption could be a few months or years. Both eruption sequences began with a small eruption. A large-scale eruption can occur a few months after the start of the eruption sequence. This is an important turning point in the eruption sequence of Shinmoedake.

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要旨：近年，胆道疾患に対する診断と治療法は著しい発展をとげてきた．胆石症や急性胆嚢炎・胆管炎などに対しては，それぞれ腹腔鏡下手術や緊急胆道減圧ドレナージが広く定着し，その治療成績は向上した．しかし，我が国における癌の種類別死亡数が6番目に多い胆道癌に対する予後は，診断，周術期管理，外科手術法が発達したにもかかわらず進行期で発見されることが多いため，未だ不良である．今回の会長講演では，胆道癌の診断と治療の現状と問題点を講演した．胆道癌で多く出現する閉塞性黄疸下肝切除後の肝再生不良の機序を分子生物学的に検証し，術前胆汁内瘻の有用性，胆道ドレナージの時期としては進展度診断を終えてから行うことの重要性を述べた．また，肝門部胆管癌，中下部胆管癌，胆嚢癌の外科治療と幽門輪温存膵頭十二指腸切除後胃内容停滞の再建経路による比較を，我々の教室の成績を基に概説した．

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A new breeding ground of Eurystomus orientalis abundus was discovered by us in Tottori Prefecture during the summer 1949.
Having intended to make clear of the breeding habits of this bird we explored the ground during the breeding season of 1950 and found that about 25 pairs were present.
During this investigation many points concerning to its nidification were made clear for the first time in Japan:
1) Nestling: down absent; mouth, inside light pink but black around the tongue; external flanges light yellow; tongue, light pink tinged with grey at the base.
2) Both parents incubate and feed young.
3) Their voice is something like gyo, gyo; gyo; gyo gyo gyo.…

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The Kirishima Volcano Group is composed of many Quaternary volcanoes occupying an area about 600km². Ohachi Volcano is a small, active stratovolcano situated at the southeastern part of the Kirishima Volcano Group. It has a considerably large crater compared to the size of its volcanic edifice, with thick agglutinates that crop out on the wall of the crater. We studied the eruptive history of Ohachi Volcano by tephrochronological method, and recognized 15 tephra deposits around the volcano. Geological and archeological data and documentary records of eruption indicate that the oldest tephra from the Ohachi Volcano is the Araso tephra (AsT) erupted in ca. AD 700. All other tephra deposits were erupted in historic time such as Katazoe tephra (KzT) in AD 788, Miyasugi tephra (MsT) in ca. AD 1000, Takaharu tephra (ThT) in AD 1235, and Takachihogawara tephra 1-11 (TgT-1 to TgT-11) in the period of AD 1250-1700. Thus, the Ohachi is a very young volcano at 1300 years old. We recognized two types of magmatic eruption : sub-plinian and vulcanian. Lava emission took place at least four times in association with sub-plinian eruptions. Among these eruptions, ThT is the most voluminous, and a pyroclastic flow was also generated. The total volume of erupted magma (volcanic edifice included) was calculated to be about 2.5×10⁸m³ (DRE). Eruption rate was not constant throughout the eruptive history of Ohachi volcano, that is, the eruptive history is conveniently divided into three stages by the eruption rate : the early stage from AD 700 to 1235 (ca. 540 years), the middle stage from AD 1236 to 1717 (480 years), and the late stage from AD 1718 up to present (290 years). This indicates that more than 80% of the total amount of magma was produced in the early stage, while the remaining 20% of magma was erupted in the middle stage. Although there are many recorded eruptions during the late stage, it is difficult to find any tephra deposits around the Ohachi Volcano, which suggests that the scale of volcanic eruption is progressively diminishing through time. The volcanic edifice of Ohachi is composed mainly of succession of thick tephra layers, some of them changed to agglutinates. Correlation of the proximal deposits to the distal tephra suggests that the volcanic edifice had grown mainly during the two eruptive stages of KzT and ThT, which are comparatively large-scale sub-plinian eruptions (order of 10⁷m³ to 10⁶m³). Hence, the most important process in generating agglutinates is rapid accumulation of voluminous tephra around the crater which are generated during sub-plinian eruptions.

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