A note on the total chromatic number of Halin graphs with maximum degree 4

AbstractIn this paper, we prove that χT(G) = 5 for any Halin graph G with Δ(G) = 4, where Δ(G) and χT(G) denote the maximal degree and the total chromatic number of G, respectively

Maternal Thermal Effects on Female Reproduction and Hatchling Phenotype in the Chinese Skink (Plestiodon chinensis)</i>

We maintained gravid Chinese skinks (Plestiodon chinensis) at three constant temperatures (25, 28 and 31 °C) during gestation, and randomly assigned eggs from each female to one of the same three temperatures for incubation to determine maternal thermal effects on female reproduction and hatchling phenotype. Maternal temperature affected egg-laying date, hatching success and hatchling linear size (snout-vent length, SVL) but not clutch size, egg size, egg component, and embryonic stage at laying. More specifically, females at higher temperatures laid eggs earlier than did those at low temperatures, eggs laid at 31 °C were less likely to hatch than those laid at 25 °C or 28 °C, and hatchlings from eggs laid at 31 °C were smaller in SVL. Our finding that maternal temperature (pre-ovipositional thermal condition) rather than incubation temperature (post-ovipositional thermal condition) affected hatching success indicated that embryos at early stages were more vulnerable to temperature than those at late stages. Our data provide an inference that moderate maternal temperatures enhance reproductive fitness in P. chinensis

Tetra­kis(μ3-2-{[1,1-bis­(hydroxy­meth­yl)-2-oxidoeth­yl]imino­meth­yl}-6-methoxy­phenol­ato)tetra­nickel(II) tetra­hydrate

The title complex, [Ni4(C12H15NO4)4]·4H2O, has crystal­lographic fourfold inversion symmetry, with each NiII ion coordinated in a slightly distorted square-pyramidal coordination environment and forming an Ni4O4 cubane-like core. In the crystal structure, inter­molecular O—H⋯O hydrogen bonds connect complex and water mol­ecules to form a three-dimensional network. The O atom of one of the unique hydroxy­methyl groups is disordered over two sites, with the ratio of occupancies being approximately 0.79:0.21

[N-(3-Meth­oxy-2-oxidobenzyl­idene-κO 2)threoninato-κ2 O 1,N](1,10-phenanthroline-κ2 N,N′)copper(II) hemihydrate

In the title complex, [Cu(C12H13NO5)(C12H8N2)]·0.5H2O, the CuII ion is five-coordinated by one N atom and two O atoms from a tridentate Schiff base ligand, derived from the condensation of l-threonine and o-vanillin, and two N atoms from a 1,10-phenanthroline ligand in a distorted square-pyramidal geometry. In the crystal, inter­molecular O—H⋯O hydrogen bonds form a one-dimensional left-handed helical structureextending parallel to [001]. The water molecule of crystallization shows half-occupancy

Bis[μ-N-(3-meth­oxy-2-oxidobenzyl­idene-1:2κ2 O 2:O 2)-l-isoleucinato-2κ2 N,O]bis­(1,10-phenanthroline-1κ2 N,N′)dinickel(II) methanol tetra­solvate trihydrate

In the title complex, [Ni2(C14H17NO4)2(C12H8N2)2]·4CH3OH·3H2O, the two NiII ions are bridged by two Schiff base anions, leading to a dinuclear complex. One NiII ion is six-coordinated by four O atoms and two N atoms of two tridentate Schiff base ligands derived from the condensation of l-isoleucine and o-vanillin. The other NiII ion is six-coordinated by four N atoms of two 1,10-phenanthroline ligands and two O atoms of the Schiff base ligands. In the crystal, inter­molecular O—H⋯O and C—H⋯O hydrogen bonds lead to a three-dimensional structure. Intra­molecular C—H⋯O hydrogen bonds are also present. One of the methyl groups of the l-isoleucinate moieties is disordered over two sets of sites with an occupancy ratio of 0.687 (19):0.313 (19) and two methanol mol­ecules are half-occupied