Experimental Study of a Novel Method of Cardiopulmonary Resuscitation Using a Combination of Percutaneous Cardiopulmonary Support and Liposome-encapsulated Hemoglobin (TRM645)

Percutaneous cardiopulmonary support (PCPS) has been applied for cardiopulmonary arrest (CPA). We have developed a novel method of cardiopulmonary resuscitation using PCPS combined with liposome-encapsulated hemoglobin (TRM645) to improve oxygen delivery to vital organs. Ventricular fibrillation was electrically induced to an adult goat for 10 min. Next, PCPS (30 ml/kg/min, V/Q: 1) was performed for 20 min. Then, external defibrillation was attempted and observed for 120 min. The TRM group (n5) was filled with 300 mL of TRM645 for the PCPS circuit. The control group (n5) was filled with the same volume of saline. The delivery of oxygen (DO2) and oxygen consumption (VO2) decreased markedly by PCPS after CPA, compared to the preoperative values. DO2 was kept at a constant level during PCPS in both groups, but VO2 slowly decreased at 5, 10, and 15 min of PCPS in the control groups, demonstrating that systemic oxygen metabolism decreased with time. In contrast, the decreases in VO2 were small in the TRM group at 5, 10, and 15 min of PCPS, demonstrating that TRM645 continuously maintained systemic oxygen consumption even at a low flow rate. AST and LDH in the TRM group were lower than the control. There were significant differences at 120 min after the restoration of spontaneous circulation (p&#60;0.05).</p

Crustal structure and growth of the Forearc region of Izu-Ogasawara arc

（独）海洋研究開発機構(JAMSTEC)では、2002年から伊豆・小笠原・マリアナ島弧において、大陸地殻の生成過程を明らかにすることを目的に構造調査を進め、現在の島弧地殻のボリュームより多くの玄武岩マグマが必要で島弧地殻を生成する過程でマフィックな島弧地殻の一部をマントル内に戻していること（Takahashi et al., 2007, 2008; Tatsumi et al., 2008）、火山フロントと背弧側の地殻の厚さ分布には相関があり過去のリフティングが検出されたこと（Kodaira et al., 2009）などがわかってきた。前弧域の地殻に関しては、厚い地殻と薄い地殻が存在すること（Takahashi et al., 2011）、地磁気異常から島弧的な構造があること（Yamazaki and Yuasa, 1998）がわかっているが、地殻構造から実証されていなかった。前弧域の地殻構造を求め、地殻進化の影響をどの程度受けているのか、前弧域の島弧成長を明らかにするために、（独）海洋研究開発機構の深海調査船「かいれい」を用いて人工地震探査を行った。 地震探査の測線は、新黒瀬からスミス海脚、第二東鳥島海丘、大町海山を通って、小笠原トラフに至る。得られた速度構造から前弧域は25km程度の地殻の厚い部分と10～15km程度の薄い部分があることが明らかになった。厚い地殻は、北緯32.5度付近、スミス海脚、第二東鳥島海丘、大町海山の下に分布する。新黒瀬側は厚い地殻を持たない。大町海山の内部には異常に厚い下部地殻が分布する。薄い地殻が分布するところでは、堆積層が厚く地殻の厚さの半分近くを占める。大町海山以外の地殻が厚く分布するところでは、P波速度6km/sの速度コンターが上に凸、7km/sの速度コンターが下に凸の形状を示す。火山フロントに沿った地殻構造では、むしろ6km/s以下の速度を持つ層が厚いことが示されている（Kodaira et al., 2007）。これは、前弧域下の島弧地殻は、火山フロント下と比較して未分化な物質を多く含むことを示唆おり、過去の掘削結果とも整合する（e.g., Taylor, 1992）。前弧海盆下の島弧地殻の分布は、地磁気異常の空間分布（Yamazaki and Yuasa, 1998）とよく合致する。新黒瀬周辺で見られる地磁気異常は、本研究から明らかになった地殻が薄く地殻全体が盛り上がっている形状と合致する。伊豆小笠原島弧の本州弧への衝突が新黒瀬の浅海部を作っているものと示唆される。SCG66-03発表要旨 / 日本地球惑星科学連合2012年大会（2012年5月20日～5月25日, 幕張メッセ国際会議場） / 日本惑星科学連合の許諾に基づき本文ファイルを掲

Executive summary: "Mantle Frontier" workshop

The workshop on “Reaching the Mantle Frontier: Moho and Beyond� was held at the Broad Branch Road Campus of the Carnegie Institution of Washington on 9–11 September 2010. The workshop attracted seventy-four scientists and engineers from academia and industry in North America, Asia, and Europe.Reaching and sampling the mantle through penetration of the entire oceanic crust and the Mohorovi�ić discontinuity (Moho) has been a longstanding goal of the Earth science community. The Moho is a seismic transition, often sharp, from a region with compressional wave velocities (Vp) less than 7.5 km s-1 to velocities ~8 km s-1. It is interpreted in many tectonic settings, and particularly in tectonic exposures of oceanic lower crust, as the transition from igneous crust to mantle rocks that are the residues of melt extraction. Revealing the in situ geological meaning of the Moho is the heart of the Mohole project. Documenting ocean-crust exchanges and the nature and extent of the subseafloor biosphere have also become integral components of the endeavor. The purpose of the “Mantle Frontier� workshop was to identify key scientific objectives associated with innovative technology solutions along with associated timelines and costs for developments and implementation of this grandchallenge

CO2-rich komatiitic melt inclusions in Cr-spinels within beach sand from Gorgona Island, Colombia

Author Posting. © The Author(s), 2009. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Earth and Planetary Science Letters 288 (2009): 33-43, doi:10.1016/j.epsl.2009.09.005.The volatile content of komatiite is a key to constrain the thermal and chemical evolution of the deep Earth. We report the volatile contents with major and trace element compositions of ~ 80 melt inclusions in chromian spinels (Cr-spinels) from beach sands on Gorgona Island, Colombia. Gorgona Island is a ~ 90 Ma volcanic island, where picrites and the youngest komatiites known on the Earth are present. Melt inclusions are classified into three types on the basis of their host Cr-spinel compositions: low Ti (P type), high Ti with high Cr# (K1 type) and high Ti with low Cr# (K2 type). Chemical variations of melt inclusions in the Cr-spinels cover all of the island's lava types. P-type inclusions mainly occur in the picrites, K1-type in high-TiO2 komatiites (some enriched basalts: E-basalts) and K2-type in low-TiO2 komatiites. The H2O and CO2 contents of melt inclusions within Cr-spinels from the beach sand are highly variable (H2O: 0.03–0.9 wt.%; CO2: 40–4000 ppm). Evaluation of volatile content is not entirely successful because of compositional alterations of the original melt by degassing, seawater/brine assimilation and post-entrapment modification of certain elements and volatiles. However, the occurrence of many melt inclusions with low H2O/K2O ratios indicates that H2O/K2O of Gorgona komatiite is not much different from that of modern mid-oceanic ridge basalt (MORB) or oceanic island basalt. Trend of CO2/Nb and Zr/Y ratios, accounted for by two-component mixing between the least degassed primary komatiite and low-CO2/Nb evolved basalt, allow us to estimate a primary CO2/Nb ratio of 4000 ± 2200 or a CO2 content of 0.16 ± 0.09 wt.%. The determined CO2/Nb ratio is unusually high, compared to that of MORB (530). Although the presence of CO2 in the Gorgona komatiite does not affect the magma generation temperature, CO2 degassing may have contributed to the eruption of high-density magmas. High CO2/Nb and the relatively anhydrous nature of Gorgona komatiite provide possible resolution to one aspect of the hydrous komatiite debate.This work is financially supported by grants from the Japan Society for the Promotion of Science

Velocity structure of the fore-arc region of the Ogasawara Ridge and distribution of horizons

小笠原海嶺はフィリピン海プレート上の島弧地殻としては、もっとも古い島弧の一つとして島弧生成時の地殻を含む地殻が分布すると知られている（例えば、Ishizsuka et al., 2006）。これらのことは、これまでに行われてきた構造探査結果からも示唆されている。海嶺を横断する調査からは、P 波速度6.4-6.6 km/s の上部地殻とP 波速度7.0-7.2 km/s の下部地殻が同定された（Takahashi et al., 2009）。しかし、海嶺軸に沿った方向の調査からは、海洋性地殻と同等の薄い地殻の分布が明らかになり、海嶺の最浅部近傍の狭いエリアに薄い地殻が存在することが明らかになっている（Kodaira et al., 2012）。しかもその厚さは、海嶺に沿った方向に大きく変化する。一方、しんかい6500 を用いた海底観察からは、boninite、fore-arc basalt、gabbro、peridotite が分布していることが明らかになっており（Ishizuka et al.,2006）、オフィオライトの構造、つまり島弧生成前の古い海洋性地殻が存在しているのではないか、と議論された。太平洋プレート上の構造との共通的な特徴が地震学的に確認できるかどうか、この層序の海嶺の前弧域直下への連続性を確認するため、2011 年に構造探査を実施した。これらの構造は島弧の初期生成の鍵になるため、IODP の掘削提案も提出された。紹介する調査は、このIODP 掘削提案の事前調査の一環として行われた。調査は（独）海洋研究開発機構の深海調査船「かいれい」を用いて行われた。マルチチャンネル反射法探査データのみならず（444channels, 25 m group interval）、海底地震計を用いた屈折法探査データも取得した。使用したエアガンは総容量7800 cu.in.のAPG ガンで、反射法探査向けには50 m、屈折法探査向けには200 m 間隔で発振した。測線長は約250 kmで、海底地震計43 台を5 km 間隔で設置した。得られた反射断面は非常に複雑な様相を呈する。少なくとも測線全体に渡って連続する反射面は見当たらない。いくつかの小海山があるが、これらの海山はなだらかな傾斜をしており、また火山フロント上の海山で見られるようなすそ野に広がる厚い堆積物も見られない。海底地震計の記録も、海底地震計直上から40?60 km の範囲でしか初動が読み取れず、複雑な速度構造が分布していることを示唆している。peridotite が広く存在していれば、8 km/s 前後の見かけ速度の走時が読み取れるはずだが、そのような部分は、測線の中央部付近の海嶺の一部に限定された。また、初動走時が不連続でジャンプするような低速度層の分布を示唆する記録も得られた。浅部の構造は深部と比較して均質であり、5.0-5.5 km/s、6.0-7.0 km/s の層が広範囲に分布している。以前の調査結果によれば、上盤側の地殻と海洋性地殻が接している場所に本発表の測線があり、部分的に上盤側のperidotite 層がこの測線直下に分布しているものと思われる。海底から約4 秒のところには、比較的明瞭な反射波が読み取れた。本発表では、トモグラフィックインバージョンによる暫定的に決定した速度構造と反射面の分布を紹介する。また、反射記録断面から上盤側の反射面と沈み込む太平洋プレート上面からの反射波を同定し、オフィオライト構造を確認するために、得られた速度構造と海洋性地殻の類似性、相違性を確認する。B21-12発表要旨, 日本地震学会2012年度秋季大会（2012年10月16日～19日, 北海道函館市

Velocity structure along the Ogasawara Ridge fore-arc region

The Ogasawara Ridge is known as one of oldest arc on the Philippine Sea Plate. This Ridge has very complex structure. According to refraction survey crossing the ridge, the ridge has a very thin granitic layer with velocity of approximately 6 km/s, an andesitic layer with a velocity of 6.4-6.6 km/s and gabbroic layer with a velocity of 7.0-7.2 km/s (Takahashi et al., 2009). On the other hand, the thin crust with a thickness less than 10 km distributes beneath the shallowest topographic peak (Kodaira et al., 2012). According to geologic studies, boninites, fore-arc basalts, gabbros and peridotites were collected by Shinkai 6500 dives on the trench slope (Ishizuka et al., 2006). The observation is expected to be helpful for subduction initiation studies because these geological sequences are similar characteristics of ophiolite. Therefore, we carried out refraction survey using ocean bottom seismographs (OBSs) along the strike of the Ogasawara Ridge to detect such geological sequences using seismic imaging technique as one of site surveys for IBM drilling. This survey was carried by using R/V “Kairei” of Japan Agency for Marine-Earth Science and Technology (JAMSTEC) in 2011 and we collected not only OBSs data but also multi-channel reflection data (MCSs) on a seismic line with a length of 250 km. Total 43 OBSs were deployed at an interval of 5 km and the airgun shooting with a total capacity of 7800 cu.in. was 200 m interval. First arrivals on OBS records are traced to offsets of 40-60 km, and the data is generally noisy suggesting complexity of fore-arc structure. If there is peridotite layer in the hanging wall side, the refractions with apparent velocity of about 8 km/s are identified, and discontinuous jump of the first arrivals should be at far side due to subducting oceanic crust. The observed refractions, however, have apparent velocities between 6.0-7.5 km/s to far side. Refractions with an apparent velocity of 8 km/s seem to be limited in narrow area. In addition, the jump of first arrivals is also identified on some OBS records, but it is not common character for whole of the line. We introduce the tentative tomographic image obtained by using first arrivals and reflection points distribution. Although the plate boundary structure is very complex, the structure of the hanging wall is relatively homogeneous. Then, we compared the structural image obtained by this study with geologic observation.Poster abstract T51D-2620 presented at 2012 Fall Meeting, AGU, San Francisco, Calif., 3-7 Dec

Voluminous magma formation for the 30-ka Aira caldera-forming eruption in SW Japan: contributions of crust-derived felsic and mafic magmas

Understanding the origin, assembly, and evolution of voluminous magma that erupts in catastrophic caldera-forming eruptions (CCFEs) is a community imperative. A CCFE of the Aira caldera at 30 ka discharged over 350 km3 of magma, which can be grouped into petrographically and geochemically distinct types: voluminous rhyolite, small amounts of rhyodacite, and andesite magmas. To further understand the magma plumbing system of the Aira CCFE, we examined the geochemical characteristics of whole rock and plagioclase from its eruptive deposits. The trace element and 87Sr/86Sr signatures recorded in the plagioclase phenocrysts of these magmas indicate that the three magmas were originally produced by partially melting an identical source rock, which was estimated to be a mafic amphibolite with an 87Sr/86Sr signature of ∼0.7055 that comprised the lower crust. Melting of mafic amphibolite produced both felsic and mafic magmas by low and high degrees of partial melting, respectively. The mafic magma assimilated uppermost crustal materials and crystallized to produce an andesite magma type. The andesitic magma consists of phenocrysts (∼39 vol%) and melt with a dacitic (∼70 wt% SiO2) composition. The felsic magma mixed with ∼10% of the andesite magma and crystallized, forming the rhyolite magma. The mixing between the andesite and rhyolite magmas before the Aira CCFE produced the rhyodacite magma. The 30-ka Aira CCFE magmas were generated only by melting two kinds of crustal materials with different geochemical characteristics and had geochemical variations due to different conditions of partial melting and mixing between various crustal melts. The lack of definitive evidence of the mantle component mixing with the Aira CCFE magmas suggests that the mantle-derived magmas worked only as a heat source for crustal melting

JASMINE: Near-infrared astrometry and time-series photometry science

The Japan Astrometry Satellite Mission for INfrared Exploration (JASMINE) is a planned M-class science space mission by the Institute of Space and Astronautical Science, the Japan Aerospace Exploration Agency. JASMINE has two main science goals. One is Galactic archaeology with a Galactic Center survey, which aims to reveal the Milky Way’s central core structure and formation history from Gaia-level (∼25 ${\mu}$as) astrometry in the near-infrared (NIR) Hw band (1.0–1.6 ${\mu}$m). The other is an exoplanet survey, which aims to discover transiting Earth-like exoplanets in the habitable zone from NIR time-series photometry of M dwarfs when the Galactic Center is not accessible. We introduce the mission, review many science objectives, and present the instrument concept. JASMINE will be the first dedicated NIR astrometry space mission and provide precise astrometric information on the stars in the Galactic Center, taking advantage of the significantly lower extinction in the NIR. The precise astrometry is obtained by taking many short-exposure images. Hence, the JASMINE Galactic Center survey data will be valuable for studies of exoplanet transits, asteroseismology, variable stars, and microlensing studies, including discovery of (intermediate-mass) black holes. We highlight a swath of such potential science, and also describe synergies with other missions

Petrography, K-Ar age, and chemistry of Yoshino-dai lavas in the Aira caldera

The Aira caldera was formed about 22, 000 years ago in association with large-scale pyroclastic eruptions of more than 400km^3 felsic ejecta. Petrography was described and major/trace element compositions and K-Ar ages were determined for Aira precaldera lavas in the Yoshino-dai area, in order to examine mechanisms by which a series of the Aira precaldera and climactic magmas were produced. Precaldera lavas in the Yoshino-dai area mainly consist of augite-olivine basalt and two-pyroxene andesite, as previous workers indicated. K-Ar ages of precaldera basalts and andesites are >0.5 Ma and, in contrast, K-Ar age of precaldera rhyolite is <0.5 Ma and eruptions of precaldera dacites and minor pyroclastic flows may have occurred after ～ 0.5 Ma. The precaldera and climactic ejecta show a single chemical trend with the cusp at SiO^2～65 wt. % for some elements. It follows that a series of Aira precaldera magmas was not produced by a single process such as fractional crystallization from basaltic magmas or two-end-member mixing between basaltic magmas and rhyolitic magmas. The generation of a series of Aira precaldera magmas requires at least two processes; production of basaltic to andesitic magmas before ～ 0.5 Ma and of dacitic to rhyolitic magmas after ～ 0.5 Ma. The possibility that the state of the magmatic system beneath the Aira caldera may have changed at ～ 0.5 Ma remains