An elementary proof is given of localization for linear operators H=Ho+λV, with Ho translation invariant, or periodic, and V(.) a random potential, in energy regimes which for weak disorder (λ→0) are close to the unperturbed spectrum σ(Ho). The analysis is within the approach introduced in the recent study of localization at high disorder by Aizenman and Molchanov [AM]; the localization regimes...

A number of viewpoints on how a cell can be modelled are discussed in this paper in light of the ability it has to process information. The paper begins with a very brief summary of four general types of computation: sequential, parallel, distributed, and emergent. These form the general framework from which a number of comparisons are made. Several metaphors are introduced to enable reflection...

After summarizing briefly some numerical results for four-dimensional supersymmetric SU(2) Yang-Mills quantum mechanics, we review a recent study of systems with an infinite number of colours. We study in detail a particular supersymmetric matrix model which exhibits a phase transition, strong-weak duality, and a rich structure of supersymmetric vacua. In the planar and strong coupling limits, ...

The capacity of a freeway segment should be measured only when it is an active bottleneck. The properties of flows at active freeway bottlenecks have a bearing on both the definition of capacity and the procedure of capacity analysis. Past studies have examined the flow features at bottlenecks on several freeways in Toronto, Canada, and San Diego, California. This study examined 27 active bottl...

When teaching an introductory zoology course, it is always entertaining to show students some specimens of the only described species of placozoans—Trichoplax adhaerens, a tiny, simple, nearly worldwide marine organism (Figure 1) [1,2]. The inevitable disbelief—those are animals?—leads naturally to enumerating the shared derived features of all animals (Box 1) and in turn to discussing the rela...

T iny, membrane-bound packets of tinted protein, called melano-somes, dictate the color of human skin. Defi ciencies in melanosome production underlie pigmentation diseases, so it is important to understand how melanosomes are generated. But melanosomes are just one example of a larger family of lyso-some-related organelles, many of which are associated with pathologies when they are functional...

introduction: since lectures’ experiences can help university managers in improving educational situation, this study was carried out to determine faculty lecturers’ attitudes towards the educational situation at kermanshah university of medical sciences. materials and methods: this study is a descriptive–analytical one. a two-part questionnaire was employed for data collection. the first part ...