EQUULEUS (EQUilibriUm Lunar-Earth point 6U Spacecraft) will be the world's smallest spacecraft to explore the Earth–Moon Lagrange point. It is being jointly developed by JAXA (Japan Aerospace ...Exploration Agency) and the University of Tokyo, and will be launched by NASA's Space Launch System Exploration Mission-1. The spacecraft will fly to a libration orbit around the Earth–Moon L2 point (EML2) and will demonstrate low-energy trajectory-control techniques within the Sun—Earth—Moon region for the first time by a nano-class spacecraft. EQUULEUS also carries three scientific observation missions: imaging of Earth's plasmasphere by extreme ultraviolet wavelength, lunar impact flash observation on the far side of the moon, and micrometeoroid flux measurements in the cis-lunar region. While all these missions have their own scientific objectives, they will also contribute to future human activity and/or infrastructure development in the cis-lunar region. Most parts of the spacecraft system use commercial off-the-shelf components, or are designed based on the experiences of various past space missions, with the exception of the newly developed water resistojet propulsion system. EQUULEUS uses X-band frequency for deep space telecommunication. Japanese deep space antennas (64-m and 34-m) will be nominally used for spacecraft operation, and support from the deep space network of JPL (Jet Propulsion Laboratory) is also being planned, especially for the initial phase of operation. The spacecraft will fly to EML2 in less than one year, and will remain there for scientific observations until shortly before the depletion of the onboard propellant, when the spacecraft will leave the orbit for space-debris compliance.
Isolation of asubclavian ...arteryとは一側の鎖骨下動脈が大動脈弓より分離し動脈管によって同側の肺動脈と接続するもので,まれな発生異常である.我々はII群完全大血管転位症に合併した本症を経験した.症例は2歳6カ月の女児で,動脈側スイッチ手術を施行したが,緊張した肺動脈により冠動脈が圧迫されたため左室不全をきたして術中死した.剖検にて右鎖骨下動脈のisolationが発見され,これが術中出血および術直後の肺動脈緊張の原因と考えられた.術前の大動脈造影をretrospectiveに観察すると,右鎖骨下動脈は大動脈から分岐しておらず,椎骨動脈からの側副血行により逆行性に造影され右肺動脈につながる像が認められた.文献的には右大動脈弓に合併した左鎖骨下動脈のisolationが多く,右鎖骨下動脈のisolationは,我々の調べ得た限りでは,これまでに自験例を含め9例の報告を認めるのみであった.
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