Biocatalytic synthesis of the conjugated bridging ligand tetrapyrido[3,2-a:2',3'-c:3'',2''-h:2'",3'"-j]phenazine (tpphz) and a dinuclear ruthenium complex

We have synthesized a fully conjugated aromatic bridging ligand, tetrapyrido[3,2-a:2',3'-c:3',2'-h:2' ",3'"-j]phenazine (tpphz), and a dinuclear ruthenium complex using Hematin as a biocatalyst.     

Stereochemistry in trivalent nitrogen compounds. 40. Torsional barriers in N-2,4-dinitrobenzenesulfenylbenzimidazoles.

N-2,4-Dinitrobenzenesulfenylbenzimidazoles exhibit substantial barriers to torsion about the sulfur-nitrogen bond ($\text{ca}$ 19 kcal/mole).     

Prevention and detection of diabetic embryopathy

Congenital anomalies are more common in the offspring of women with type 1 and type 2 diabetes mellitus. Herein we define those anomalies more commonly found in the offspring of women with diabetes mellitus, and examine the role of hyperglycemia in their pathogenesis. We then discuss methods for the optimal screening and detection of embryopathy. We conclude by presenting evidence in support of preconception diabetes care to lower the risk of fetal anomalies in women with diabetes mellitus.     

Influence of EDA-pi interactions in drug encapsulation using nanospheres

We have evaluated the influence of aromatic and hydrophobic interactions on the strength and selectivity of encapsulation using polymeric nanospheres.     

Stereoselective reactions of a (-)-quinic acid-derived enone: application to the synthesis of the core of scyphostatin

[reaction: see text] A (-)-quinic acid-derived enone, with the trans-1,2-diol protected as a 2,3-dimethoxybutanediyldioxy ketal, provides an excellent template for further highly stereoselective elaboration as exemplified by its conversion into the core of scyphostatin, a potent inhibitor of neutral sphingomyelinase.     

Initial Chain Algebras on Pseudotrees

We investigate a new class of Boolean algebra, called initial chain algebras on pseudotrees. We discuss the relationship between this class and other classes of Boolean algebras. Every interval algebra, and hence every countable Boolean algebra, is an initial chain algebra. Every initial chain algebra on a tree is a superatomic Boolean algebra, and every initial chain algebra on a pseudotree is a minimally-generated Boolean algebra.We show that a free product of two infinite Boolean algebras is an initial chain algebra if and only if both factors are countable.     

Construction of LU Factors of the Basis to Reduce Build-Up during Simplex Iterations

Algorithms for the inversion of a sparse square matrix have generally been designed with the aim of minimizing the number of calculations required to factorize the matrix and to solve for one or more right-hand sides. This usually involves attempting to minimize the number of non-zeros in the factors of the inverse. An inversion routine for use in the product-form simplex method must satisfy a rather different requirement. The inverse is updated during iterations to reflect changes in the basis, and additional non-zeros created by updating become significant. We consider the use of various forms of the Hellerman-Rarick P4 inversion algorithm in conjunction with the Forrest-Tomlin update of the factors, and suggest a heuristic for selection between these forms during the inversion process.     

Photovoltaic Performance Enhancement in Dye-Sensitized Solar Cells with Periodic Surface Relief Structures

One-dimensional and two-dimensional periodic TiO₂ relief structures were incorporated in dye-sensitized solar cells. The periodic TiO₂ structures were fabricated using surface relief gratings photoinscribed on azobenzene functionalized polymer films as templates and TiO₂ sol-gel solution. Enhancement of power conversion of the solar cells made with the relief TiO₂ structures was achieved. This enhancement suggests that the relief TiO₂ structures can offer efficient light-trapping with the increased effective optical-path length in the solar cells.