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The isotopic signature of atmospheric carbon offers a unique tracer for the history of the Martian atmosphere and the origin of organic matter on Mars. Photolysis of CO$_{2}$ is known to induce strong isotopic fractionation of carbon between CO$_{2}$ and CO. However, its effect on the carbon isotopic compositions in the Martian atmosphere remains uncertain. Here we develop a 1-D photochemical model considering isotopic fractionation via photolysis of CO$_{2}$ to estimate the vertical profiles of the carbon isotopic compositions of CO and CO$_{2}$ in the Martian atmosphere. We find that CO is depleted in $^{13}$C compared with CO$_{2}$ at each altitude due to the fractionation via CO$_{2}$ photolysis: the minimum value of $\delta ^{13}$C in CO is about $-170$ per mil under the standard eddy diffusion setting. This result supports the hypothesis that fractionated atmospheric CO is responsible for the production of the $^{13}$C-depleted organic carbon in Martian sediments detected by Curiosity Rover through the conversion of CO into organic materials and their deposition on the surface. The photolysis and transport-induced fractionation of CO we report here leads to a $\sim 15$ % decrease in the amount of inferred atmospheric loss when combined with the present-day fractionation of the atmosphere and previous studies of carbon escape to space. The fractionated isotopic composition of CO in the Martian atmosphere may be observed by ExoMars Trace Gas Orbiter (TGO) and ground-based telescopes, and escaping ion species produced by the fractionated carbon-bearing species may be detected by Martian Moons eXploration (MMX) in the future., Comment: 13 pages, 6 figures

Supplemental material, sj-docx-1-cll-10.1177_09636897221143364 for Clinical Impact of Melphalan Pharmacokinetics on Transplantation Outcomes in Children Undergoing Hematopoietic Stem Cell Transplantation by Ryo Maemura, Manabu Wakamatsu, Kana Matsumoto, Hirotoshi Sakaguchi, Nao Yoshida, Asahito Hama, Taro Yoshida, Shunsuke Miwata, Hironobu Kitazawa, Kotaro Narita, Shinsuke Kataoka, Daisuke Ichikawa, Motoharu Hamada, Rieko Taniguchi, Kyogo Suzuki, Nozomu Kawashima, Eri Nishikawa, Atsushi Narita, Yusuke Okuno, Nobuhiro Nishio, Koji Kato, Seiji Kojima, Kunihiko Morita, Hideki Muramatsu and Yoshiyuki Takahashi in Cell Transplantation

はじめに：大腸穿孔患者に対して，術前の重症度に応じた適切医療機関を選択できる指標があれば，効率的な治療が遂行できると考えられる．方法：SOFA score（以下，SS），APACHE-II score（以下，AS），POSSUM scoreの術前評価であるPhysiological score（以下，PS）から，ROC曲線を用いて最適な術前重症度評価法を検討する．また，ロジット回帰分析から逆推定した予測値を用いて，施設ごとの治療水準を比較評価できる客観的方法を提案する．対象：当施設で手術を施行した医原性穿孔を除く47例（男性24例，女性23例，平均65.9歳）．転帰は生存40例（85.1％），在院死亡7例（術死5例）であった．成績：転帰との関連は各スコアともP＜0.001と有意差を認めた．ROC曲線ではAS，PSとも曲線下面積0.95と同等かつ優れた評価能を有した．SSの曲線下面積は0.90であった．生存の確率を50％として逆推定した予測値はAS 21，PS 43であり，当施設ではこれら以上の値では極めて予後不良であった．考察：ASとPSはいずれも術前重症度評価法として適切と考えられた．施設ごとの治療水準を量る客観的方法として，AS, PSと転帰のROC曲線から算出した予測値は理解しやすい．予測値の設定は，各施設での治療遂行あるいはより優れた治療水準を有する医療機関への転院の是非を検討する判断材料となり，患者の重症度に応じた治療水準を有する医療機関を選択できるようになれば，救命率の向上に寄与できると考えられる．