Novel,stereoselective tricyclization of a dienyne by titanium aryloxide centers

Titanium centers supported by aryloxide ligation mediate the tricyclization of a dienyne via intramolecular insertion of an olefin into the titanium-vinyl bond of a titanacyclopent-2-ene.     

Regiodependent luminescence quenching of biotinylated N-sulfonyl-acridinium-9-carboxamides by avidin

[reaction: see text] Biotin was conjugated to chemiluminescent N-sulfonylacridinium-9-carboxamides at the N-10 or 9-position carboxamide. Upon binding to avidin, the light output of the N-10 derivative (8) was quenched up to 92% upon triggering with basic peroxide, while the 9-position carboxamide conjugate (9) was quenched only 33%. The utility of this effect was demonstrated in a model homogeneous chemiluminescence assay.     

Massively parallel computation of large-scale spatial price equilibrium models with discriminatory ad valorem tariffs

In this paper, we develop a perfectly competitive spatial equilibrium model in price and quantity variables in the presence of discriminatory ad valorem tariffs, a widely used trade policy instrument. We derive the equilibrium conditions and formulate them as a variational inequality problem. An algorithm is then proposed for the computation of the equilibrium pattern and convergence results established. The algorithm resolves the problem into very simple subproblems, each of which can be solved simultaneously and in closed form. Finally, the algorithm is implemented on the massively parallel Thinking Machines CM-2 and CM-5 architectures, known as the Connection Machines, and numerical results presented.