Australian National University

About: Australian National University is a education organization based out in Canberra, Australian Capital Territory, Australia. It is known for research contribution in the topics: Population & Galaxy. The organization has 34419 authors who have published 109261 publications receiving 4315448 citations. The organization is also known as: The Australian National University & ANU.

New insights into nucleosome and chromatin structure: an ordered state or a disordered affair?

Abstract: Chromatin compaction has profound implications for the regulation of transcription, replication and DNA repair. Changes in nucleosome structure and stability — due to the incorporation of variant histones and post-translational modifications of histones — affect chromatin compaction. Chromatin structures are not nearly as uniform as previously assumed, which should be taken into account in the context of specific biological functions.

On blocking rules for the bootstrap with dependent data

Abstract: SUMMARY We address the issue of optimal block choice in applications of the block bootstrap to dependent data It is shown that optimal block size depends significantly on context, being equal to n"/3, n"/4 and nll5 in the cases of variance or bias estimation, estimation of a onesided distribution function, and estimation of a two-sided distribution function, respectively A clear intuitive explanation of this phenomenon is given, together with outlines of theoretical arguments in specific cases It is shown that these orders of magnitude of block sizes can be used to produce a simple, practical rule for selecting block size empirically That technique is explored numerically

Sustainable Intensification of Agriculture for Human Prosperity and Global Sustainability

Abstract: There is an ongoing debate on what constitutes sustainable intensification of agriculture (SIA). In this paper, we propose that a paradigm for sustainable intensification can be defined and translated into an operational framework for agricultural development. We argue that this paradigm must now be defined—at all scales—in the context of rapidly rising global environmental changes in the Anthropocene, while focusing on eradicating poverty and hunger and contributing to human wellbeing. The criteria and approach we propose, for a paradigm shift towards sustainable intensification of agriculture, integrates the dual and interdependent goals of using sustainable practices to meet rising human needs while contributing to resilience and sustainability of landscapes, the biosphere, and the Earth system. Both of these, in turn, are required to sustain the future viability of agriculture. This paradigm shift aims at repositioning world agriculture from its current role as the world’s single largest driver of global environmental change, to becoming a key contributor of a global transition to a sustainable world within a safe operating space on Earth.

Growth of early continental crust by partial melting of eclogite

Abstract: The tectonic setting in which the first continental crust formed, and the extent to which modern processes of arc magmatism at convergent plate margins were operative on the early Earth, are matters of debate1,2. Geochemical studies have shown that felsic rocks in both Archaean high-grade metamorphic (‘grey gneiss’) and low-grade granite-greenstone terranes are comprised dominantly of sodium-rich granitoids of the tonalite-trondhjemite-granodiorite (TTG) suite of rocks3,4,5,6,7. Here we present direct experimental evidence showing that partial melting of hydrous basalt in the eclogite facies produces granitoid liquids with major- and trace-element compositions equivalent to Archaean TTG, including the low Nb/Ta and high Zr/Sm ratios of ‘average’ Archaean TTG8, but from a source with initially subchondritic Nb/Ta. In modern environments, basalts with low Nb/Ta form by partial melting of subduction-modified depleted mantle9,10, notably in intraoceanic arc settings in the forearc11,12 and back-arc13,14 regimes. These observations suggest that TTG magmatism may have taken place beneath granite-greenstone complexes developing along Archaean intraoceanic island arcs by imbricate thrust-stacking15 and tectonic accretion16 of a diversity of subduction-related terranes. Partial melting accompanying dehydration of these generally basaltic source materials at the base of thickened, ‘arc-like’ crust would produce compositionally appropriate TTG granitoids in equilibrium with eclogite residues.