We investigate permutations in terms of their cycle structure and descent set. To do this, we generalize the classical bijection of Gessel and Reutenauer to deal with permutations that have some ascending and some descending blocks. We then provide the first bijective proofs of some known results. We also solve some problems posed in [4] by Eriksen, Freij, and Wästlund, who study derangements t...

We give character formulae for the positive energy unitary irreducible representations of the N-extended D=4 conformal superalgebras su(2,2/N). Using these we also derive decompositions of long superfields as they descend to the unitarity threshold. These results are also applicable to irreps of the complex Lie superalgebras sl(4/N). Our derivations use results from the representation theory of...

We give character formulae for the positive energy unitary irreducible representations of the N-extended D=4 conformal superalgebras su(2,2/N). Using these we also derive decompositions of long superfields as they descend to the unitarity threshold. These results are also applicable to irreps of the complex Lie superalgebras sl(4/N). Our derivations use results from the representation theory of...

Following intraocular injection of cholera toxin subunit B (CTB), optic afferents to the dorsal pontine region were observed in Mongolian gerbils, Chilean degus, and laboratory rats. CTB-positive optic axons emerge at the caudal pole of the superior colliculus, descend through the periaqueductal gray, and innervate the lateral parabrachial nucleus. This projection appears to be a continuation o...

We introduce a new clustering method based on unsupervised binary trees. It is a three stages procedure, which performs on a first stage recursive binary splits reducing the heterogeneity of the data within the new subsamples. On the second stage (pruning) adjacent nodes are considered to be aggregated. Finally, on the third stage (joining) similar clusters are joined even if they do not descen...

Background: It is estimated that 15 million births occur every year to adolescents. This represents about 11%of all births each year. The global average rate of births per 1000 females aged 15-19 years is 65. A range of social, cultural, biological and service delivery factors contribute to the high levels of adolescent pregnancy and childbirth. This study was conducted to determine the causes ...

We give character formulae for the positive energy unitary irreducible representations of the N-extended D=4 conformal superalgebras su(2,2/N). Using these we also derive decompositions of long superfields as they descend to the unitarity threshold. These results are also applicable to irreps of the complex Lie superalgebras sl(4/N). Our derivations use results from the representation theory of...

In this paper, we present three kinds of broadcasting tree for the even dimensional uni-directional hypercube (UHC) and its applications (ASCEND/DESCEND algorithms and bitonic sorting). For the n-dimensional UHC, under the constant evaluation model, one of our all-port broadcasting trees has height n + 1, which is optimal. Whereas the best one of our one-port broadcasting trees needs at most 1 ...

We demonstrate theoretically that the periodic multilayer Epoxy/Glass supports acoustic frequency bands sensitive to the changes of temperature. Due to the strong variation of the sound velocity in the Epoxy, the width of the band gaps and the midgap frequencies descend when the temperature passes from 0 to 100°C. The transmittance spectrum shows that this system can be useful as a sound filter...

the rectum. In the aard-vark the testes occupy an intermediate position within the inguinal canal, but here there is reason to believe that they descend into the scrotum during the mating season. The testes of active creatures like ungulates, carnivores, and primates lie within a post-penile scrotum, where they are free from violent changes in pressure and are kept in the position of greatest s...