Synthesis of C-2 Unsubstituted Furanonaphthoquinones

Four C-2 unsubstituted naphtho[2,3-b]furan-4,9-quinones were prepared via the corresponding phthalides obtained by directed ortho-metalation-based route.     

The tiling C*-algebra viewed as a tight inverse semigroup algebra

We realize Kellendonk’s C*-algebra of an aperiodic tiling as the tight C*-algebra of the inverse semigroup associated to the tiling, thus providing further evidence that the tight C*-algebra is a good candidate to be the natural associative algebra to go along with an inverse semigroup.     

An analysis of the dependence of saccadic latency on target position and target characteristics in human subjects

Background  

Predictions from conduction velocity data for primate retinal ganglion cell axons indicate that the conduction time to the lateral geniculate nucleus for stimulation of peripheral retina should be no longer than for stimulation of central retina. On this basis, the latency of saccadic eye movements should not increase for more peripherally located targets. However, previous studies have reported relatively very large increases, which has the implication of a very considerable increase in central processing time for the saccade-generating system.     

Hamiltonian groups are color-graph-hamiltonian

A group Γ is said to be color -graph -hamiltonian if Γ has a minimal generating set Δ such that the Cayley color graph D_Δ(Γ) is hamiltonian. It is shown that every hamiltonian group is color -graph -hamiltonian.     

Locally Hausdorff tight groupoids generalised

We extend Exel’s ample tight groupoid construction to non-ample groupoids, even in the general locally Hausdorff case.

     

Sliding block codes between shift spaces over infinite alphabets

Recently Ott, Tomforde and Willis introduced a notion of one‐sided shifts over infinite alphabets and proposed a definition for sliding block codes between such shift spaces. In this work we propose a more general definition for sliding block codes between Ott–Tomforde–Willis shift spaces and then we prove Curtis–Hedlund–Lyndon type theorems for them, finding sufficient and necessary conditions under which the class of the sliding block codes coincides with the class of continuous shift‐commuting maps.     

Synthesis of 2-Substituted Furanonaphthoquinones Using Directed Metalation and Cross Coupling Reactions

A synthetic method for the preparation of C-2 substituted furanonaphthoquinones from ortholithium-benzamide and the 2-furan-carboxaldehyde derivative is described. Four 2-alkyl-furanonaphthoquinones and the 2-phenyl-substituted were prepared via phathalide. This route has been shown to be general application to the synthesis of furanonaphthoquinones.     

Production of monoclonal antibodies against a cell surface concanavalin A binding glycoprotein

Concanavalin A-binding (Con-A)-binding cell surface glycoproteins were isolated, via Con A-affinity chromatography, from Triton X-100-solubilized Chinese hamster ovary (CHO) cell plasma membranes. The Con A binding glycoproteins isolated in this manner displayed a significantly different profile on sodium dodecyl sulfate--polyacrylamide gels than did the Triton-soluble surface components, which were not retarded by the Con-A-Sepharose column. [125I]-Con A overlays of the pooled column fractions displayed on sodium dodecyl sulfate--polyacrylamide gel electro-phoresis (SDS-PAGE) demonstrated that there were virtually no Con A receptors associated with the unretarded peak released by the Con A-Sepharose column, whereas the material which was bound and specifically eluted from the Con A-Sepharose column with the sugar hapten alpha-methyl-D-mannopyranoside contained at least 15 prominent bands which bound [125I]-Con A. In order to produce monoclonal antibodies against various cell surface Con A receptors, Balb/c mice were immunized with the pooled Con A receptor fraction. Following immunization spleens were excised from the animals and single spleen cell suspensions were fused with mouse myeloma P3/X63-Ag8 cells. Numerous hybridoma clones were subsequently picked on the basis of their ability to secrete antibody which could bind to both live and glutaraldehyde-fixed CHO cells as well as to the Triton-soluble fraction isolated from the CHO plasma membrane fraction. Antibody from two of these clones was able to precipitate a single [125I]-labeled CHO surface component of approximately 265,000 daltons.