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Placentals are the most abundant mammals that have diversified into every niche for vertebrates and dominated the world's terrestrial biotas in the Cenozoic. A critical event in mammalian history is the divergence of eutherians, the clade inclusive of all living placentals, from the metatherian-marsupial clade (1-8). Here we report the discovery of a new eutherian of 160 Myr from the Jurassic of China, which extends the first appearance of the eutherian-placental clade by about 35 Myr from the previous record, reducing and resolving a discrepancy between the previous fossil record and the molecular estimate for the placental-marsupial divergence (9-13). This mammal has scansorial forelimb features, and provides the ancestral condition for dental and other anatomical features of eutherians., Class Mammalia Clade Boreosphenida (14) Infraclass Eutheria Order and family incertae sedis Juramaia sinensis gen. et sp. nov. Etymology. Jura, Jurassic; mala, mother, in reference to placental affinities; sinensis, of [...]

Author(s): Zhe-Xi Luo (corresponding author) [1, 2]; Qing-Jin Meng (corresponding author) [3]; David M. Grossnickle [2]; Di Liu [3]; April I. Neander [1]; Yu-Guang Zhang [3]; Qiang Ji [4] Stem [...]

Stem mammaliaforms are Mesozoic forerunners to mammals, and they offer critical evidence for the anatomical evolution and ecological diversification during the earliest mammalian history. Two new eleutherodonts from the Late Jurassic period have skin membranes and skeletal features that are adapted for gliding. Characteristics of their digits provide evidence of roosting behaviour, as in dermopterans and bats, and their feet have a calcaneal calcar to support the uropagatium as in bats. The new volant taxa are phylogenetically nested with arboreal eleutherodonts. Together, they show an evolutionary experimentation similar to the iterative evolutions of gliders within arboreal groups of marsupial and placental mammals. However, gliding eleutherodonts possess rigid interclavicleclavicle structures, convergent to the avian furculum, and they retain shoulder girdle plesiomorphies of mammaliaforms and monotremes. Forelimb mobility required by gliding occurs at the acromionclavicle and glenohumeral joints, is different from and convergent to the shoulder mobility at the pivotal claviclesternal joint in marsupial and placental gliders., Author(s): Qing-Jin Meng [1]; David M. Grossnickle [2]; Di Liu [1]; Yu-Guang Zhang [1]; April I. Neander [3]; Qiang Ji [4]; Zhe-Xi Luo (corresponding author) [2, 3] Mammaliaforms of the [...]

The maleo­nitrile moiety of the title compound, (2 Z)-2,3-bis­[(4-nitro­benzyl)­sulfanyl]­but-2-ene­di­nitrile, C18H12N4O4S2, is almost planar. The two benzene rings are nearly parallel to each other and perpendicular to the maleo­nitrile plane. Intermolecular S⃛S and π-π interactions are observed in the crystal structure. [ABSTRACT FROM AUTHOR]

Abstract: Two new molecular magnets, [RBzPyN(CH3)2][Ni(mnt)2] [mnt2−=maleonitriledithiolate; [RBzPyN(CH3)2]+=1-(4′-R-benzyl)-4-dimethylaminopyridinium; R=CN(1), F(2)], with unusual magnetic properties have been prepared and characterized. Both 1 and 2 form a 3D network structure in which the [Ni(mnt)2]− anions form a 1D magnetic chain for 1 and a stepwise stack for 2 via weak π…π stacking interactions, C…C or C…N short interactions between the neighboring anions. Magnetic susceptibility measurements in the temperature range 1.8–300K indicated that 1 and 2 show unusual spin gap transition around 30K and 110K, respectively. The transition for 1 and 2 is the second-order phase transition as determined by the capacity measurement. [Copyright &y& Elsevier]

In the title compound, tetra-kis[μ(3)-(2-pyrid-yl)methano-lato]tetra-kis[bromido(methanol)cobalt(III)] tetra-bromide 2-(hydroxy-meth-yl)pyridine tetra-solvate dihydrate, [Co(4)Br(4)(C(6)H(6)NO)(4)(CH(3)OH)(4)]Br(4)·4C(6)H(7)NO(4)·2H(2)O, the cation comprises a [Co(4)O(4)] cubane-type core ( symmetry). The four Co(III) ions and bridging O atoms from four (2-pyrid-yl)methano-late anions are located at alternating vertices of the cube, with bromide ions and methanol ligands on the exterior of the core, completing a distorted octa-hedral geometry. The structure is stablized by inter-molecular O-H⋯Br and O-H⋯O inter-actions.

Two donor-acceptor molecules with different pi-electron conjugative units, 1-((10-methyl-10H-phenothiazin-3-yl)ethynyl)anthracene-9,10-dione (AqMp) and 1,1'-(10-methyl-10H-phenothiazine-3,7-diyl)bis(ethyne-2,1-diyl)dianthracene-9,10-dione (Aq2Mp), have been synthesized and investigated for their photochemical and electrochemical properties. Density functional theory (DFT) calculations provide insights into their molecular geometry, electronic structures, and properties. These studies satisfactorily explain the electrochemistry of the two compounds and indicate that larger conjugative effect leads to smaller HOMO-LUMO gap (Eg) in Aq2Mp. Both compounds show ICT and pi --> pi* transitions in the UV-visible range in solution, and Aq2Mp has a bathochromic shift and shows higher oscillator strength of the absorption, which has been verified by time-dependent DFT (TDDFT) calculations. The differences between AqMp and Aq2Mp indicate that the structural and conjugative effects have great influence on the electronic properties of the molecules.