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1. Molecules with ALMA at Planet-forming Scales (MAPS). XII. Inferring the C/O and S/H Ratios in Protoplanetary Disks with Sulfur Molecules

   https://doi.org/10.3847/1538-4365/ac2583  

   Le Gal, Romane ; Öberg, Karin I. ; Teague, Richard ; Loomis, Ryan A. ; Law, Charles J. ; Walsh, Catherine ; Bergin, Edwin A. ; Ménard, François ; Wilner, David J. ; Andrews, Sean M. ; et al ( November 2021 , The Astrophysical Journal Supplement Series)
2. Molecules with ALMA at Planet-forming Scales (MAPS). VI. Distribution of the Small Organics HCN, C 2 H, and H 2 CO

   https://doi.org/10.3847/1538-4365/ac1440  

   Guzmán, Viviana V. ; Bergner, Jennifer B. ; Law, Charles J. ; Öberg, Karin I. ; Walsh, Catherine ; Cataldi, Gianni ; Aikawa, Yuri ; Bergin, Edwin A. ; Czekala, Ian ; Huang, Jane ; et al ( November 2021 , The Astrophysical Journal Supplement Series)
3. Molecules with ALMA at Planet-forming Scales (MAPS). IX. Distribution and Properties of the Large Organic Molecules HC 3 N, CH 3 CN, and c-C 3 H 2

   https://doi.org/10.3847/1538-4365/ac1441  

   Ilee, John D. ; Walsh, Catherine ; Booth, Alice S. ; Aikawa, Yuri ; Andrews, Sean M. ; Bae, Jaehan ; Bergin, Edwin A. ; Bergner, Jennifer B. ; Bosman, Arthur D. ; Cataldi, Gianni ; et al ( November 2021 , The Astrophysical Journal Supplement Series)

   Abstract The precursors to larger, biologically relevant molecules are detected throughout interstellar space, but determining the presence and properties of these molecules during planet formation requires observations of protoplanetary disks at high angular resolution and sensitivity. Here, we present 0.″3 observations of HC 3 N, CH 3 CN, and c -C 3 H 2 in five protoplanetary disks observed as part of the Molecules with ALMA at Planet-forming Scales (MAPS) Large Program. We robustly detect all molecules in four of the disks (GM Aur, AS 209, HD 163296, and MWC 480) with tentative detections of c -C 3 H 2 and CH 3 CN in IM Lup. We observe a range of morphologies—central peaks, single or double rings—with no clear correlation in morphology between molecule or disk. Emission is generally compact and on scales comparable with the millimeter dust continuum. We perform both disk-integrated and radially resolved rotational diagram analysis to derive column densities and rotational temperatures. The latter reveals 5–10 times more column density in the inner 50–100 au of the disks when compared with the disk-integrated analysis. We demonstrate that CH 3 CN originates from lower relative heights in the disks when compared with HC 3 N, in some cases directly tracing the disk midplane. Finally, we find good agreement between the ratio of small to large nitriles in the outer disks and comets. Our results indicate that the protoplanetary disks studied here are host to significant reservoirs of large organic molecules, and that this planet- and comet-building material can be chemically similar to that in our own solar system. This paper is part of the MAPS special issue of the Astrophysical Journal Supplement. 

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4. L oo p D e l t a : E m b e dd i n g L o c a li t y - a w a r e O pp o r t un i s t i c D e l t a C o m p r e ss i o n i n I n li n e D e dup li c a t i o n f o r Hi g h l y E ffic i e n t D a t a R e du c t i o n

   Zhang, Yucheng ; Jiang, Hong ; Feng, Dan ; Jiang Nan ; Qui, Taorong ; Huang, Wei ( July 2023 , USENIX annual technical conference)

   A s a c om pl e men t t o da ta d edupli cat ion , de lta c om p ress i on fu r- t he r r edu c es t h e dat a vo l u m e by c o m pr e ssi n g n o n - dup li c a t e d ata chunk s r e l a t iv e to t h e i r s i m il a r chunk s (bas e chunk s). H ow ever, ex is t i n g p o s t - d e dup li c a t i o n d e l t a c o m pr e ssi o n a p- p ro a ches fo r bac kup s t or ag e e i t h e r su ffe r f ro m t h e l ow s i m - il a r i t y b e twee n m any de te c ted c hun ks o r m i ss so me po t e n - t i a l s i m il a r c hunks , o r su ffer f r om l ow (ba ckup and r es t ore ) th r oug hpu t du e t o extr a I/ Os f or r e a d i n g b a se c hun ks o r a dd a dd i t i on a l s e r v i c e - d i s r up t ive op e r a t i on s to b a ck up s ys t em s. I n t h i s pa p e r, w e pr opo se L oop D e l t a t o a dd ress the above - m e n t i on e d prob l e m s by an e nha nced em b e ddi n g d e l t a c o m p - r e ss i on sc heme i n d e dup li c a t i on i n a non - i n t ru s ive way. T h e e nha nce d d elt a c o mpr ess ion s che m e co m b in e s f our key t e c h - ni qu e s : (1) du a l - l o c a li t y - b a s e d s i m il a r i t y t r a c k i n g to d e t ect po t e n t i a l si m il a r chun k s b y e x p l o i t i n g both l o g i c a l and ph y - s i c a l l o c a li t y, ( 2 ) l o c a li t y - a wa r e pr e f e t c h i n g to pr efe tc h ba se c hun ks to a vo i d ex t ra I/ Os fo r r e a d i n g ba s e chun ks on t h e w r i t e p at h , (3) c a che -aware fil t e r to avo i d ext r a I/Os f or b a se c hunk s on t he read p at h, a nd (4) i nver sed de l ta co mpressi on t o perf orm de lt a co mpress i o n fo r d at a chunk s t hat a re o th e r wi se f o r b i dd e n to s er ve as ba se c hunk s by r ew r i t i n g t e c hn i qu e s d e s i g n e d t o i m p r ove r es t o re pe rf o rma nc e. E x p e r i m e n t a l re su lts indi ca te t hat L oop D e l t a i ncr ea se s t he c o m pr e ss i o n r a t i o by 1 .2410 .97 t i m e s on t op of d e dup li c a - t i on , wi t hou t no t a b l y a ffe c t i n g th e ba ck up th rou ghpu t, a nd i t i m p r ove s t he res to re p er fo r m an ce b y 1.23.57 t i m e 

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5. Fulde-Ferrell-Larkin-Ovchinnikov superconductivity in the layered organic superconductor β”−(BEDT−TTF)4[(H3O)Ga(C2O4)3]C6H5NO2

   https://doi.org/10.1103/PhysRevB.97.144505  

   Uji, S. ; Iida, Y. ; Sugiura, S. ; Isono, T. ; Sugii, K. ; Kikugawa, N. ; Terashima, T. ; Yasuzuka, S. ; Akutsu, H. ; Nakazawa, Y. ; et al ( April 2018 , Physical Review B)