In this paper we give a simple two stage algorithm for approximating a point cloud S ⊂ Rm by a simplicial complex K. The first stage is an iterative fitting procedure that generalizes k-means clustering, while the second stage involves deleting redundant simplices. A form of dimension reduction of S is obtained as a consequence.

[1] One of the biggest assumptions, and a source of some of the biggest uncertainties in earthquake hazard estimation is the role of fault segmentation in controlling large earthquake ruptures. Here we apply a new model which produces sequences of elastodynamic earthquake events on complex segmented fault systems, and use these simulations to quantify the variation of large events. We find a nu...

The cause of the high genetic variability in the major histocompatibility complex (MHC) is not entirely clear. Recently, two reports suggest that female mice prefer to mate with males different from them at the MHC. A model of female choice appropriate for those observations is developed here. Female choice can in fact reduce the observed proportions of homozygotes, maintain genetic polymorphis...

This review discusses the prospects for understanding the genetic basis of complex traits in humans. We take the view that work done on Drosophila melanogaster can serve as a model for understanding complex traits in humans, and the literature on this model system, as well as on humans, is reviewed. The prospects for success in understanding the genetic basis of complex traits depend, in part, ...

The heterogeneous nature of a complex network determines the roles of each node in the network that are quite different. Mechanisms of complex networks such as spreading dynamics, cascading reactions, and network synchronization are highly affected by a tiny fraction of so-called important nodes. Node importance ranking is thus of great theoretical and practical significance. Network entropy is...

It is well-known that, within ERP paradigms of sentence processing, semantically anomalous words elicit N400 effects. Less clear, however, is what happens after the N400. In some cases N400 effects are followed by Late Positive Complexes (LPC), whereas in other cases such effects are lacking. We investigated several factors which could affect the LPC, such as contextual constraint, inter-indivi...

Combining information from multiple SNPs may capture a greater amount of genetic variation than from the sum of individual SNP effects and help identifying missing heritability. Regions may capture variation from multiple common variants of small effect, multiple rare variants or a combination of both. We describe regional heritability mapping of human cognition. Measures of crystallised (gc) a...

Populations that have experienced long periods of geographic isolation will diverge over time. The application of highthroughput sequencing technologies to study the genomes of related taxa now allows us to quantify, at a fine scale, the consequences of this divergence across the genome. Throughout a number of studies, a notable pattern has emerged. In many cases, estimates of differentiation a...

BACKGROUND Defects of the mitochondrial genome are recognised as common causes of genetic disease. Sequencing of large portions or even the entire mitochondrial genome is routine in many laboratories for the investigation of mitochondrial disease. However, establishing whether a detected sequence change is polymorphic or pathogenic is still a major difficulty because of its highly polymorphic n...

Male Lutzomyia longipalpis of two types from Bolivia were compared using isozyme electrophoresis and wing morphometry. One sample (ex Chiflonkaka Cave, alt. 2800 m at Toro Toro, Charcas Province, Potosi Department) was 'two-spot' phenotype males (i.e. tergites III and IV with paired pale patches of pheromone glands), whereas two other locality samples (Apa Apa and Imanaco, Sud Yungas Province, ...