HE segregational behavior of Drosophila chromosomes in the first meiotic Tdivision of the oocyte is quite different from that expected from the classical picture of the independent assortment of nonhomologous chromosomes and the regular segregation of homologous chromosomes. Under appropriate circumstances, nonhomologous chromosomes may segregate very regularly to opposite poles of the spindle ...

The human α-globin gene cluster is located on chromosome 16 pterp13.3, and is arranged in the order, 5’ζ2-ψζ1-ψα2-ψα1-α2-α1-θ1-3’. Recent reexamination of the ψα2 gene revealed that it is expressed at a very low level, and was renamed as mu-globin gene. The cluster was thought to result from duplication events that occurred more than 300 million years ago. Unequal homologous recombinations are ...

Teaching  English  in  an  Iranian  and  Islamic  culture  poses  complex  questions  for  both  teachers and learners. In this paper, the authors intend to shed light on what it means to teach English as a  foreign  language  (TEFL)  in  an  Islamic-Iranian  context.  Having  reviewed  the  colonial  and postmodern views of English language teaching, the authors took a look beyond the current ...

This paper presents the application of metaheuristic methods to the minimum crossing number problem for the first time. These algorithms including particle swarm optimization, improved ray optimization, colliding bodies optimization and enhanced colliding bodies optimization. For each method, a pseudo code is provided. The crossing number problem is NP-hard and has important applications in eng...

The number of selectively neutral polymorphic sites in a random sample of genes can be affected by ancestral selectively favored substitutions at linked loci. The degree to which this happens depends on when in the history of the sample the selected substitutions happen, the strength of selection and the amount of crossing over between the sampled locus and the loci at which the selected substi...

In this correspondence, we present new results on the reconstruction of two-dimensional signals from zero crossing or threshold crossing information. Specifically, we develop new theoretical results which state conditions under which two-dimensional bandlimited signals are uniquely specified to within a scale factor with this information. Unlike previous results in this area, our new results do...

Let Rn = max0≤j≤n Sj − Sn be a random walk Sn reflected in its maximum. We give necessary and sufficient conditions for finiteness of passage times of Rn above horizontal or certain curved (power law) boundaries. Necessary and sufficient conditions are also given for the finiteness of the expected passage time of Rn above linear and square root boundaries. 2000 MSC Subject Classifications: prim...

Improved bounds for the crossing number of the mesh of trees graph, Mn, are derived. In particular, we derive a new lower bound of 5n log n−44n 80 ‡ which improves on the previous bound of Leighton [11] by a constant factor, and an upper bound of (log n− 10 3 )n 2 + 8n− 20 3 . In addition, we construct drawings of Mn which achieve the upper bound number of crossings. We also prove that the cros...