The restoration of vegetation on coal gangue mountains has always been an area concern, and therefore, important research. Liupanshui city in Guizhou province, China, a large number mountains, for this reason, was chosen studying succession these sites. Vetiveria zizanioides is known to accelerate the shorten community timeframes. Because this, we investigated different successional stages afte...

In August of 1852 Dr. Walter Channing, professor of obstetrics and medical jurisprudence at Harvard Medical School, was about to finish an extensive tour of Europe, having left Boston early in May of that year. He was sixtysix at the time, and almost a half century had passed since his previous trip to that continent where as a medical student he studied in Edinburgh and London. The trip had ta...

The Deligne-Simpson problem is formulated like this: give necessary and sufficient conditions for the choice of the conjugacy classes Cj ⊂ SL(n,C) or cj ⊂ sl(n,C) so that there exist irreducible (p + 1)-tuples of matrices Mj ∈ Cj or Aj ∈ cj satisfying the equality M1 . . .Mp+1 = I or A1 + . . .+Ap+1 = 0. We solve the problem for generic eigenvalues with the exception of the case of matrices Mj ...

In the current issue of the Journal, Tu et al. (1) show convincingly that if there is no correlation between birth weight and blood pressure but both are positively correlated with current weight (which they are), then adjustment for current weight can induce a negative correlation between birth weight and blood pressure. This demonstration may be important in stimulating epidemiologists to ret...

Theory predicts that the temporal stability of productivity, measured as the ratio of the mean to the standard deviation of community biomass, increases with species richness and evenness. We used experimental species mixtures of grassland plants to test this hypothesis and identified the mechanisms involved. Additionally, we tested whether biodiversity, productivity and temporal stability were...

The article evaluates the dependence of most common indices species diversity on sample size and determines their ability to differentiate between different types ecosystems, with a special emphasis discriminating natural anthropogenic ecosystems. An approach adjusting reduce was also proposed. study conducted in seven ecosystems: four were three anthropogenically transformed. Samples soil anim...

The amount of variation in species composition among sampling units or beta diversity has become a primary tool for connecting the spatial structure of species assemblages to ecological processes. Many different measures of beta diversity have been developed. Among them, the total variance in the community composition matrix has been proposed as a single-number estimate of beta diversity. In th...