This study examined infants’ use of picture-location contingencies and spatiotemporal regularity in forming visual expectations. Ninety-six 3-month-olds watched an event sequence in which pictures appeared at 3 locations, either in regular leftcenter-right alternation or in a random center-side pattern. For half of the infants, the content of the central picture was predictive of the location o...

One of the most commonly observed surface structures on the prokaryotic cell envelopes is monomolecular crystalline array of proteinaceous subunits termed Surface Layers or S-layers. Due their self assembly ability and the highly ordered, regular structure down to the nanometer scale, S-layers were demonstrated to possess a great potential for nanobiotechnological applications. Some probiotic b...

This paper concerns power series of an arithmetic nature that arise in the analysis of divide-and-conquer algorithms. Two key notions are studied: that of B-regular sequence and that of Mahlerian sequence with their associated power series. Firstly we emphasize the link between rational series over the alphabet fx0;x1;:::;xB?1g and B-regular series. Secondly we extend the theorem of Christol, K...

A model for cleaning a graph with brushes was recently introduced. Let α = (v1, v2, . . . , vn) be a permutation of the vertices of G; for each vertex vi let N (vi) = {j : vjvi ∈ E and j > i} and N−(vi) = {j : vjvi ∈ E and j < i}; finally let bα(G) = ∑n i=1 max{|N+(vi)|−|N−(vi)|, 0}. The Broom number is given by B(G) = maxα bα(G). We consider the Broom number of d-regular graphs, focusing on th...

Finding optimum and near optimum edit scripts between an XML document and a schema is essential to correcting invalid XML documents. In this paper, we consider finding K optimum edit scripts between an XML document and a regular tree grammar. We first prove that the problem is NP-hard. We next show a pseudopolynomial-time algorithm for solving the problem.

A numeration system based on a strictly increasing sequence of positive integers u0 = 1, u1, u2, . . . expresses a non-negative integer n as a sum n = ∑i j=0 ajuj . In this case we say the string aiai−1 · · · a1a0 is a representation for n. If gcd(u0, u1, . . .) = g, then every sufficiently large multiple of g has some representation. If the lexicographic ordering on the representations is the ...

Highly expressed genes in many bacteria and small eukaryotes often have a strong compositional bias, in terms of codon usage. Two widely used numerical indices, the codon adaptation index (CAI) and the codon usage, use this bias to predict the expression level of genes. Both indices are based on fairly simple assumptions about which genes are most highly expressed, which were known when they we...

The Shortest Common Supersequence problem (SCS for short) consists in finding a shortest common supersequence of a finite set of words on a fixed alphabet Σ. It is well-known that its decision version denoted [SR8] in [3] is NP-complete. Many variants have been studied in the literature. In this paper we settle the complexity of two such variants of SCS where inputs do not contain identical con...

A strongly regular graph is called trivial if it or its complement is a union of disjoint cliques. We prove that the parameters n; k; ; of nontrivial strongly regular graphs satisfy = k=n+ o (n) and = k=n+ o (n) : It follows, in particular, that every in…nite family of nontrivial strongly regular graphs is quasi-random in the sense of Chung, Graham and Wilson. 1 Introduction Our graph-theoretic...

We describe a recipe for generating normal ideals on successors of singular cardinals. We show that these ideals are related to many weakenings of that have appeared in the literature. Our main purpose, however, is to provide an organized list of open questions related to these ideals. Throughout this note, we will let λ denote the successor of a singular cardinal μ. We will also let χ denote s...