Self-assembly of oligomeric porphyrin rings

A cobalt porphyrin equipped with two different but geometrically complementary pyridine ligands self-assembles to form an unusually stable complex with approximately 12 porphyrin monomers arranged in a macrocyclic array.     

Solution conformational preferences of glutaric, 3‐hydroxyglutaric, 3‐methylglutaric acid,and their mono‐ and dianions

Conformational preferences of glutaric, 3‐hydroxyglutaric and 3‐methylglutaric acid, and their mono‐ and dianions have been investigated with the aid of NMR spectroscopy. In contrast to succinic acid, glutaric acid displays essentially statistical conformational equilibria in polar and non‐polar solutions of high and low hydrogen‐bonding ability with no clear evidence for intramolecular hydrogen‐bonding interactions. The acid ionization constant ratios, K ₁/K₂, in D₂O and DMSO of glutaric, 3‐hydroxyglutaric, and 3‐methylglutaric acids also indicate that intramolecular interactions are much less important than, or indeed insignificant, for shorter‐chain acids. FTIR studies on 3‐methylglutaric acid indicate some preference for either association with solvent or dimerization, depending on the solvent, rather than intramolecular hydrogen bonding. Copyright © 2008 John Wiley & Sons, Ltd.     

The Relation of Generalized Scalar-Tensor Theory with the 5D Space-Time-Matter Theory

The relationship between cosmological solutionsof five-dimensional Space-Time-Matter (STM) theory anda Generalized Scalar-Tensor (GST) theory is investigatedin which the cosmological term Lambda depends not only on a scalar field but also onits time derivative .Identification of these solutions allows us to solve forthe functional form of the cosmological term, and mayhave relevance for the early Universe.     

What is the Cause of Inertia?

The question of the cause of inertial reaction forces and the validity of Mach's principle are investigated. A recent claim that the cause of inertial reaction forces can be attributed to an interaction of the electrical charge of elementary particles with the hypothetical quantum mechanical zero-point fluctuation electromagnetic field is shown to be untenable. It fails to correspond to reality because the coupling of electric charge to the electromagnetic field cannot be made to mimic plausibly the universal coupling of gravity and inertia to the stress-energy-momentum (i.e., matter) tensor. The gravitational explanation of the origin of inertial forces is then briefly laid out, and various important features of it explored in the last half-century are addressed.     

A fluidized bed process for electron sterilization of powders

A small capacity (100 g.s⁻¹) pilot system is described for presentation of powders and fine aggregates at high velocity, to an electron beam. Electron beam dose rate is continuously monitored in real time, while the thickness of the fluidized bed used to pneumatically transport the product can be monitored and controlled using beta-gauge techniques. Using electron paramagnetic resonance (EPR) techniques, alanine power mixed with the product is used for precise determination of dose delivered to the powder stream. Thin film dosimeters transported in the bed are also used for dose determination. Results with a variety of products are presented using both dose rate and velocity as the independent variables. Lethality data for the bioburdens present in several powdered foodstuffs are discussed.     

The martingale method: Introductory sketch and access to the literature

Since 1975 there has developed a powerful and sophisticated theory of statistical inference for point processes known as the ‘martingale method’. Because it is based on deep and in many cases technical results in the (French) general theory of stochastic processes, it has remained inaccessible to many who might usefully apply it. Yet the fundamental ideas (as opposed to the details, which can be formidable) are not hopelessly arcane; our purposes here are to describe the theory in a manner that reveals its underlying conceptual simplicity (although oversimplified, (6) below is the essential idea), to illustrate it with three examples, and to give some points of entry into the complex and now rather extensive literature. This is not a guide to application, much less even an incomplete development of the theory, but merely (so to speak) a silhoutte.     

An algorithm for optimal minimax routing in ATM networks

Asynchronous Transfer Mode (ATM) has been adopted by the CCITT as the transport mode in which Broadband ISDN will be based. In this paper, we formulate the problem of routing cells in an ATM network as an optimization problem. The objective is to minimize the largest cell loss probability among all links. The constraints correspond to a multicommodity network flow problem with gains. An algorithm to determine a global optimal flow assignment is presented. The minimax routing algorithm was implemented and tested on several sample networks. The computational experiments show that the algorithm is computationally efficient.Supported by NSF grant NCR 92-23148.