MuxViz: A Tool for Multilayer Analysis and Visualization of Networks

Multilayer relationships among entities and information about entities must be accompanied by the means to analyze, visualize, and obtain insights from such data. We present open-source software (muxViz) that contains a collection of algorithms for the analysis of multilayer networks, which are an important way to represent a large variety of complex systems throughout science and engineering. We demonstrate the ability of muxViz to analyze and interactively visualize multilayer data using empirical genetic, neuronal, and transportation networks. Our software is available at https://github.com/manlius/muxViz.Comment: 18 pages, 10 figures (text of the accepted manuscript

Values and Heritage Conservation: Research Report, The Getty Conservation Institute, Los Angeles

Researches values and benefits of cultural heritage conservation undertaken by GCI through its Agora initiative as a means of articulating and furthering ideas that have emerged from the conservation field in recent years

HT Camelopardalis: The simplest intermediate polar spin pulse

The intermediate polar HT Cam is unusual in that it shows no evidence for dense absorption in its spectrum. We analyse an XMM-Newton observation of this star, which confirms the absence of absorption and shows that the X-ray spin-pulse is energy independent. The modulation arises solely from occultation effects and can be reproduced by a simple geometrical model in which the lower accretion footprint is fainter than the upper one. We suggest that the lack of opacity in the accretion columns of HT Cam, and also of EX Hya and V1025 Cen, results from a low accretion rate owing to their being below the cataclysmic variable period gap.Comment: 5 pages, 6 figures, accepted for publication in MNRA

Spectroscopic diagnostics of dust formation and evolution in classical nova ejecta

A fraction of classical novae form dust during the early stages of their outbursts. The classical CO nova V5668 Sgr (Nova Sgr. 2015b) underwent a deep photometric minimum about 100 days after outburst that was covered across the spectrum. A similar event was observed for an earlier CO nova, V705 Cas (Nova Cas 1993) and a less optically significant event for the more recent CO nova V339 Del (Nova Del 2013). This study provides a "compare and contrast" of these events to better understand the very dynamical event of dust formation. We show the effect of dust formation on multiwavelength high resolution line profiles in the interval 1200\AA\ - 9200\AA\ using a biconical ballistic structure that has been applied in our previous studies of the ejecta. We find that both V5668 Sgr and V339 Del can be modeled using a grey opacity for the dust, indicating fairly large grains (at least 0.1 micron) and that the persistent asymmetries of the line profiles in late time spectra, up to 650 days after the event for V5668 Sgr and 866 days for V339 Del, point to the survival of the dust well into the transparent, nebular stage of the ejecta evolution. This is a general method for assessing the properties of dust forming novae well after the infrared is completely transparent in the ejecta.Comment: 15 pages 14 figures, accepted for publication in A&A, 2018 June 2

Nonadditivity of intermolecular forces - Effects on the third virial coefficient

Effects of nonadditive three body forces on third virial coefficien

A note on the appearance of self-dual Yang-Mills fields in integrable hierarchies

A family of mappings from the solution spaces of certain generalized Drinfeld-Sokolov hierarchies to the self-dual Yang-Mills system on R^{2,2} is described. This provides an extension of the well-known relationship between self-dual connections and integrable hierarchies of AKNS and Drinfeld-Sokolov type

Abell 370: A Cluster with a Pronounced Triaxial Morphology

We here combine Sunyaev-Zel'dovich effect, X-ray observations and spectroscopic redshifts of member galaxies, to constrain the intrinsic three-dimensional shape of the galaxy cluster: Abell 370. The cluster turns out to be strongly elongated along the l.o.s., with two (or more) substructures in the process of merging. Spectroscopy further suggests that the process must be taking place at a small angle respect to the l.o.s.Comment: 7 pages, 2 figures. Contribution to the Proceedings of the COSPAR Scientific Assembly, E1.2 "Clusters of Galaxies: New Insights from XMM-Newton, Chandra and INTEGRAL", Paris (France), July 19-20, 2004. Accepted for publication in Advances in Space Researc

Changes in co-existence mechanisms along a long-term soil chronosequence revealed by functional trait diversity

1. Functional trait diversity can reveal mechanisms of species co-existence in plant communities. Few studies have tested whether functional diversity for foliar traits related to resource use strategy increases or decreases with declining soil phosphorus (P) in forest communities. 2. We quantified tree basal area and four foliar functional traits (i.e. nitrogen (N), phosphorus (P), thickness and tissue density) for all woody species along the c. 120 kyr Franz Josef soil chronosequence in cool temperate rainforest, where strong shifts occur in light and soil nutrient availability (i.e. total soil P declines from 805 to 100 mg g–1). We combined the abundance and trait data in functional diversity indices to quantify trait convergence and divergence, in an effort to determine whether mechanisms of co-existence change with soil fertility. 3. Relationships between species trait means and total soil N and P were examined using multiple regression, with and without weighting of species abundances. We used Rao’s quadratic entropy to quantify functional diversity at the plot scale, then compared this with random expectation, using a null model that randomizes abundances across species within plots. Taxonomic diversity was measured using Simpson’s Diversity. Relationships between functional and taxonomic diversity and total soil P were examined using jackknife linear regression. 4. Leaf N and P declined and leaf thickness and density increased monotonically with declining total soil P along the sequence; these relationships were unaffected by abundance-weighting of species in the analyses. Inclusion of total soil N did not improve predictions of trait means. All measures of diversity calculated from presence/absence data were unrelated to total soil N and P. There was no evidence for a relationship between Rao values using quantitative abundances and total soil P. However, there was a strongly positive relationship between Rao, expressed relative to random expectation, and total soil P, indicating trait convergence of dominant species as soil P declined. 5. Synthesis: Our results demonstrate that at high fertility dominant species differ in resource use strategy, but as soil fertility declines over the long-term, dominant species increasingly converge on a resource-retentive strategy. This suggests that differentiation in resource use strategy is required for co-existence at high fertility but not in low fertility ecosystems