Results 71 to 80 of about 215,212 (170)
Proceedings of the Royal Society of London. Series B: Biological Sciences, 1998 Evolutionary changes in the development of shell-attached retractor muscles in gastropods are of fundamental importance to theories about the early evolution and subsequent diversification of this molluscan class.
L. Page
semanticscholar +1 more source
Dynamic expression of ancient and novel molluscan shell genes during ecological transitions [PDF]
, 2007 Background: The Mollusca constitute one of the most morphologically and ecologically diverse metazoan phyla, occupying a wide range of marine, terrestrial and freshwater habitats.
Degnan, Bernard M +2 more
core +4 more sources
Gastropod classification and taxonomy [PDF]
, 2015 Gastropods are a large and highly diversified class within the phylum Mollusca. Many gastropods possess a shell whereas some are without shells. The shelled gastropods are also called univalves.
Mohamed, K S, Venkatesan, V
core
Developmental expression of COE across the Metazoa supports a conserved role in neuronal cell-type specification and mesodermal development [PDF]
, 2010 The transcription factor COE (collier/olfactory-1/early B cell factor) is an unusual basic helix–loop–helix transcription factor as it lacks a basic domain and is maintained as a single copy gene in the genomes of all currently analysed non-vertebrate ...
A Corradi +77 more
core +2 more sources
Torsion theories of simplicial groups with truncated Moore complex [PDF]
arXiv, 2022 We introduce a linearly ordered lattice $\mu(Grp)$ of torsion theories in simplicial groups. The torsion theories are defined where the torsion/torsion-free subcategories are given by the simplicial groups with bounded above/below Moore complex, respectively.
arxiv
Mineral bridges in nacre revisited [PDF]
Recent Advances in Pearl Research, Eds., S. Watabe, K. Maeyama and
H. Nagasawa, Terrapub (Tokyo), 2013, pp. 109-123, 2012 We confirm with high-resolution techniques the existence of mineral bridges between superposed nacre tablets. In the towered nacre of both gastropods and the cephalopod Nautilus there are large bridges aligned along the tower axes, corresponding to gaps (150-200 nm) in the interlamellar membranes.
arxiv
Catastrophic failure of nacre under pure shear stresses of torsion [PDF]
, 2017 Nacre, a composite made from biogenic aragonite and proteins, exhibits excellent strength and toughness. Here, we show that nacreous sections can exhibit complete brittle fracture along the tablet interfaces at the proportional limit under pure shear ...
Alghamdi, Saleh +7 more
core +3 more sources
Dynamical torsion and torsion potential [PDF]
arXiv, 1996 We introduce a generalized tetrad which plays the role of a potential for torsion and makes torsion dynamic. Starting from the Einstein-Cartan action with torsion, we get two field equations, the Einstein equation and the torsion field equation by using the metric tensor and the torsion potential as independent variables; in the former equation the ...
arxiv
On the set of points of zero torsion for negative-torsion maps of the annulus [PDF]
arXiv, 2020 For negative-torsion maps on the annulus we show that on every $\mathcal{C}^1$ essential curve there is at least one point of zero torsion. As an outcome, we deduce that the Hausdorff dimension of the set of points of zero torsion is greater or equal 1.
arxiv
Improved side-chain torsion potentials for the Amber ff99SB protein force field
Proteins: Structure, Function, and Bioinformatics, 2010 Recent advances in hardware and software have enabled increasingly long molecular dynamics (MD) simulations of biomolecules, exposing certain limitations in the accuracy of the force fields used for such simulations and spurring efforts to refine these ...
K. Lindorff-Larsen +6 more
semanticscholar +1 more source