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   https://doi.org/10.1093/mnras/sty3421  

   Hess, Kelley M; Luber, Nicholas M; Fernández, Ximena; Gim, Hansung B; van Gorkom, J H; Momjian, Emmanuel; Gross, Julia; Meyer, Martin; Popping, Attila; Davies, Luke J; et al (December 2018, Monthly Notices of the Royal Astronomical Society)
2. A Chandra survey of z ≥ 4.5 quasars

   https://doi.org/10.1093/mnras/stab1042  

   Li, Jiang-Tao; Wang, Feige; Yang, Jinyi; Bregman, Joel N; Fan, Xiaohui; Zhang, Yuchen (May 2021, Monthly Notices of the Royal Astronomical Society)

   null (Ed.)

   ABSTRACT X-ray observations provide a unique probe of the accretion disc corona of supermassive black holes (SMBHs). In this paper, we present a uniform Chandra X-ray data analysis of a sample of 152 z ≥ 4.5 quasars. We firmly detect 46 quasars of this sample in 0.5–2 keV above 3σ and calculate the upper limits of the X-ray flux of the remaining. We also estimate the power-law photon index of the X-ray spectrum of 31 quasars. 24 of our sample quasars are detected in the FIRST or NVSS radio surveys; all of them are radio-loud. We statistically compare the X-ray properties of our z ≥ 4.5 quasars to other X-ray samples of active galactic nuclei (AGNs) at different redshifts. The relation between the rest-frame X-ray luminosity and other quasar parameters, such as the bolometric luminosity, UV luminosity, or SMBH mass, shows large scatters. These large scatters can be attributed to the narrow luminosity range at the highest redshift, the large measurement error based on relatively poor X-ray data, and the inclusion of radio-loud quasars in the sample. The LX–LUV relationship is significantly sublinear. We do not find a significant redshift evolution of the LX–LUV relation, expressed either in the slope of this relation, or the departure of individual AGNs from the best-fitting αOX–LUV relation (ΔαOX). The median value of the X-ray photon index is Γ ≈ 1.79, which does not show redshift evolution from z = 0 to z ∼ 7. The X-ray and UV properties of the most distant quasars could potentially be used as a standard candle to constrain cosmological models. The large scatter of our sample on the Hubble diagram highlights the importance of future large unbiased deep X-ray and radio surveys in using quasars in cosmological studies. 

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3. Stereoselective Synthesis of ( E )- and ( Z )-Isocyanoalkenes

   https://doi.org/10.1021/acs.orglett.2c03461  

   Tian, Huan; Holyoke, Caleb W.; Fleming, Fraser F. (December 2022, Organic Letters)
4. THE CYCLIC GRAPH OF A Z -GROUP

   https://doi.org/10.1017/S0004972720001318  

   COSTANZO, DAVID G.; LEWIS, MARK L.; SCHMIDT, STEFANO; TSEGAYE, EYOB; UDELL, GABE (January 2020, Bulletin of the Australian Mathematical Society)

   null (Ed.)

   Abstract: For a group G, we define a graph Delta (G) by letting G^#=G\{1} be the set of vertices and by drawing an edge between distinct elements x,y in G^# if and only if the subgroup is cyclic. Recall that a Z-group is a group where every Sylow subgroup is cyclic. In this short note, we investigate Delta (G) for a Z-group G. 

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5. Serendipitous Rediscovery of the Facile Cyclization of Z , Z ‐3,5‐Octadiene‐1,7‐diyne Derivatives to Afford Stable, Substituted Naphthocyclobutadienes

   https://doi.org/10.1002/cplu.201800605  

   Barker, Joshua E.; Kodama, Takuya; Song, Min K.; Frederickson, Conerd K.; Jousselin‐Oba, Tanguy; Zakharov, Lev N.; Marrot, Jérôme; Frigoli, Michel; Johnson, Richard P.; Haley, Michael M. (January 2019, ChemPlusChem)