6-Aryl- and 6,7-diaryl-1,3-dimethyl-1-perimidin-2(3)-ones: synthesis, conformational stability, crystal structure and optical properties.

6-Bromo- and 6,7-dibromo-1,3-dimethyl-1-perimidin-2(3)-ones were arylated with arylboronic acids under Suzuki-Miyaura reaction conditions to afford 6-aryl-, 6-bromo-7-aryl- and 6,7-diaryl-1,3-dimethyl-1-perimidin-2(3)-ones. A comparison of the X-ray structural parameters of -diaryl derivatives of 1,3-dimethyl-1-perimidin-2(3)-one, naphthalene and 1,8-bis(dimethylamino)naphthalene (proton sponge) was performed. Based on the data of dynamic H NMR spectroscopy and quantum-chemical calculations, barriers to /-isomerization of 6,7-diaryl-1,3-dimethyl-1-perimidin-2(3)-ones were estimated.

Spermatozoa and Spermatogenesis in the Ribbon Worm Asteronemertes gibsoni (Hoplonemertea, Oerstediidae), a Symbiont of Sea Stars.

In the phylum Nemertea, the class Hoplonemertea (former Enopla) comprises the largest number of studied species with complex spermatozoa. Asteronemertes gibsoni Chernyshev, 1991, a nemertean species having a symbiotic relationship with sea stars, is characterized by complex filiform spermatozoa. Here, spermatogenesis and spermatozoon structure in A.

Quantum Spin Dynamics Due to Strong Kitaev Interactions in the Triangular-Lattice Antiferromagnet CsCeSe_{2}.

The extraordinary properties of the Kitaev model have motivated an intense search for new physics in materials that combine geometrical and bond frustration. In this Letter, we employ inelastic neutron scattering, spin wave theory, and exact diagonalization to study the spin dynamics in the perfect triangular-lattice antiferromagnet (TLAF) CsCeSe_{2}. This material orders into a stripe phase, which is demonstrated to arise as a consequence of the off-diagonal bond-dependent terms in the spin Hamiltonian.

The diamond-silicon carbide composite Skeleton as a promising material for substrates of intense X-ray beam optics.

The paper considers the possibility of using the diamond-silicon carbide composite Skeleton with a technological coating of polycrystalline silicon as a substrate for X-ray mirrors used with powerful synchrotron radiation sources (third+ and fourth generation). Samples were studied after polishing to provide the following surface parameters: root-mean-square flatness ≃ 50 nm, micro-roughness on the frame 2 µm × 2 µm σ ≃ 0.15 nm.

Morphological and Functional Alterations in the CA1 Pyramidal Neurons of the Rat Hippocampus in the Chronic Phase of the Lithium-Pilocarpine Model of Epilepsy.

Epilepsy is known to cause alterations in neural networks. However, many details of these changes remain poorly understood. The objective of this study was to investigate changes in the properties of hippocampal CA1 pyramidal neurons and their synaptic inputs in a rat lithium-pilocarpine model of epilepsy.