Bioclimatic and masticatory influences on human cranial diversity verified by analysis of 3D morphometric homologous models.

This study analyzes the effects of bioclimate and masticatory factors on the regional variability of human cranial forms across 150 ethnic groups worldwide. Morphometric variables were generated using principal component analysis applied to 3D homologous models. Relationships between cranial form and bioclimate (temperature and precipitation) and masticatory factors (infratemporal space) were tested considering sampling bias due to past population movements during the late Pleistocene and/or early- to mid-Holocene.

Ancient Rapanui genomes reveal resilience and pre-European contact with the Americas.

Rapa Nui (also known as Easter Island) is one of the most isolated inhabited places in the world. It has captured the imagination of many owing to its archaeological record, which includes iconic megalithic statues called moai. Two prominent contentions have arisen from the extensive study of Rapa Nui.

Asymmetric Synthesis of Chiral 2-Cyclohexenones with Quaternary Stereocenters via Ene-Reductase Catalyzed Desymmetrization of 2,5-Cyclohexadienones.

Stereoselective synthesis of quaternary stereocenters represents a significant challenge in organic chemistry. Herein, we describe the use of ene-reductases OPR3 and YqjM for the efficient asymmetric synthesis of chiral 4,4-disubstituted 2-cyclohexenones via desymmetrizing hydrogenation of prochiral 4,4-disubstituted 2,5-cyclohexadienones. This transformation breaks the symmetry of the cyclohexadienone substrates, generating valuable quaternary stereocenters with high enantioselectivities (ee, up to >99%).

Loop 6 and the β-hairpin flap are structural hotspots that determine cofactor specificity in the FMN-dependent family of ene-reductases.

Flavin mononucleotide (FMN)-dependent ene-reductases constitute a large family of oxidoreductases that catalyze the enantiospecific reduction of carbon-carbon double bonds. The reducing equivalents required for substrate reduction are obtained from reduced nicotinamide by hydride transfer. Most ene-reductases significantly prefer, or exclusively accept, either NADPH or NADH.

Covariation of proximal finger and toe phalanges in Homo sapiens: A novel approach to assess covariation of serially corresponding structures.

Objectives: As hands and feet are serially repeated corresponding structures in tetrapods, the morphology of fingers and toes is expected to covary due to a shared developmental origin. The present study focuses on the covariation of the shape of proximal finger and toe phalanges of adult Homo sapiens to determine whether covariation is different in the first ray relative to the others, as its morphology is also different.

Material And Methods: Proximal phalanges of 76 individuals of unknown sex (Muséum national d'Histoire naturelle, Paris, and the Natural History Museum, London) were digitized using a surface scanner.